.
.
Math Central - mathcentral.uregina.ca
Quandaries & Queries
Q & Q
. .
topic card  

Topic:

%

list of
topics
. .
start over

12388 items are filed under this topic.
 
Page
1/2
The dimensions of a rectangle 2016-07-25
From Krunox:
A rectangle is twice as long as it is wide. Its perimeter (the sum of the lengths of its sides) is 60 cm. Find its length and width.
Answered by Penny Nom.
A cubic equation 2016-07-25
From Chinmay:
x-2x-7x+5
Answered by Penny Nom.
The number of sides of a polygon 2016-07-23
From Shriya:
All the angles of a polygon are either 155 or 140.
There are twice as many angles of 155 or 140.
Find the number of sides of the polygon

Answered by Penny Nom.
The temperature inside and outside a greenhouse 2016-07-22
From Mehzad:
Every day, the temperature in a greenhouse is at its low temperature, 70 degrees Fahrenheit, at 2 a.m. and at its high temperature, 84 degrees Fahrenheit, at 2pm. Its temperature increases linearly between 2 am and 2pm , and decreases linearly from 2 pm and to 2am. The outside temperature follows the same linear patterns, but has a low temperature of 60 degrees Fahrenheit at 2 am and a high temperature of 78 degrees Fahrenheit at 2 pm. At which of the following times will the temperature inside and outside the greenhouse be the same?

a) 8:00 am
b) 12:00 noon
c) 4:00 pm
d) The two temperatures will never be the same

Answered by Penny Nom.
Two equations with fractions 2016-07-22
From kanesh:
p/2+q/3=3

p/4+2q/3=3

Answered by Penny Nom.
Which term of this sequence has value 8? 2016-07-20
From Lauren:
Hi there

Which term in the sequence -2; -5/3; -4/3 ; -1; ... has a value of 8.

Since term 2 and 3 of this sequence contain fractions which can be converted to recurring decimals. What is the best way to work out the common difference here.

I do however understand that to work out the nth term of an arithmetic series, the following formula Tn = a + (n-1)d. In this series a = -2

Answered by Penny Nom.
Writing numbers in the form a/b 2016-07-17
From Edward:
How to write these numbers in form of a/b: -7, 0.175, -3.25, 37/10, -16, 1/3, 2.04
Answered by Penny Nom.
A congruence theorem for two right angled triangles 2016-07-17
From Sayari:
Hello. Is it possible for two right angled triangles to have the same length of base and height and a different hypotenuse? If not so, then why in the congruence criteria RHS the hypotenuse is given more importance? It can also be like- 'two triangles are congruent if they are right angled and have the same base and height.' Thank You.
Answered by Penny Nom.
The composition of a function with itself 2016-07-17
From Mel:
If f(1 + 3x) = 1 * x, solve f(f(x))
Answered by Penny Nom.
If x+y=7 and x^2+y^2=42, then xy equals? 2016-07-17
From Mehzad:
If x+y=7 and x^2+y^2=42, then xy equals?
Answered by Penny Nom.
A train from Erie to New York 2016-07-14
From carol:
a train leaves Erie with twice as many women as men. At York, 17 men get on and 16 women . How many men and women were originally on the train?off. There are now the same number of men as women
Answered by Penny Nom.
Lisa went for a run 2016-07-14
From Olive:
Lisa ran 3km north and then 4 km east what was her total distance
Answered by Penny Nom.
The perimeter and area of a shape 2016-06-30
From Scott:
If I have a 16 x 32 rectangle the square feet is 512. So if I take a rope 96 feet long , which is the lineal feet of the rectangle, and manipulate it to any shape I want does the square footage inside the rope stay at 512 square feet? Thanks in advance!
Answered by Penny Nom.
A 1.4 acre square 2016-06-28
From Jamie:
Dear Faithfullness,

I was previously to be purchasing a square 1 acre plot, which I believe was to have 209feet, 4 sides perimeter.

How big would a 1.4 acre site be?
In sq feet length ie original 209ft + (the adeed 0.4)

Answered by Penny Nom.
Triakis 2016-06-27
From Gordon:
Some authorities treat "triakis" (and related terms "dyakis", "tetrakis", etc.) as attached prefixes; others treat them as separate adjectives. Thus I see one of the Catalan solids described as both "triakistetrahedron" and "triakis tetrahedron". Which usage is correct?
Answered by Chris Fisher.
Slope 2016-06-27
From Ashiq:
What is 1% slope if length 101 feet?
Answered by Penny Nom.
Subsets 2016-06-26
From Kats:
How Many sub sets are in set k={6,7,3}
Answered by Penny Nom.
find f+g 2016-06-26
From yzabelle:
find f+g
f(x)=x^2-1
g(x)=square root of x+2

Answered by Penny Nom.
An equation involving pi 2016-06-26
From Diaz:
How would you solve :

( pie*X)/ 4 = -pie/2

I have no idea.what to do!

Answered by Penny Nom.
Simultaneous equations 2016-06-25
From sena:
2x/3+3y/2=-1
4x-5y=22

simultaneous equation

Answered by Penny Nom.
Sin squared (x) + Sin (x) - 2 2016-06-25
From Sree:
Reduce the below to a single term

Sin squared (x) + Sin (x) - 2

Thanks

Answered by Penny Nom.
An open ball is an open set? 2016-06-23
From Aqeel:
Theorem: The open ball is an open set?
Answered by Harley Weston.
Cubic feet of soil 2016-06-19
From H:
A garden is 8 ft x 7 ft that needs to raised 6 inch's How many cubic feet of soil required ? What am I missing ?

Thanks

H

Answered by Penny Nom.
Profit 2016-06-15
From Toyia:
12.87 profit from 21.99 sale. What is the percentage that was taken off the 21.99
Answered by Penny Nom.
Quadrilateral 2016-06-14
From Muhib:
Is there a quadrilateral with 0 sets of parallel sides.
Answered by Penny Nom.
A ratio of boys to girls 2016-06-12
From Jasper:
There are 600 pupils in a school. The ratio of the boys to girls in the school is 3:5 how many girls and how many boys are in the school
Answered by Penny Nom.
The difference between the ares of two rectangles 2016-06-09
From Ingrid:
I am trying to help my son with an area question.
I have the answer, from the solutions, but I cannot figure out how to teach him.

Question:

Two rectangles have lengths 13cm and 19cm respectively.
Their total area is 376cm squared.
If both their widths are whole numbers, what is the difference in their areas?

I know that this is solvable once I determine the widths of the rectangles ,
but how do I go about finding that?

Thanks for your help

Answered by Chris Fisher and Harley Weston.
Implicit differentiation 2016-06-06
From Pranay:
Is a circle x^2+y^2=2 a function? If it is not a function, why is it possible to do implicit differentiation on it?
Thanks.

Answered by Penny Nom.
The lateral side length of a cone 2016-06-05
From Diane:
Question is find the lateral side length of a right cone with area of 372 sq. cm and base circle radius of 9 cm.
Answered by Penny Nom.
20 things taken 8 at a time 2016-05-30
From Jessie:
I need all of the 8 digit combinations using the numbers 1-20.
i.e 1 2 3 4 5 6 7 8, 2 3 4 5 6 7 8 9 like wise
no number should be repeated in one combination.
Thanks
Jessie

Answered by Penny Nom.
John and Max walk to meet each other 2016-05-29
From abhay:
The speeds of John and Max are 30 km/h and 40 km/h.Initially Max is at a place L and John is at a place M. The distance between L and M is 650 km. John started his journey 3 hours earlier than Max to meet each other. If they meet each other at a place P somewhere between L and M, then the distance between P and M is?
Answered by Penny Nom.
A barn roof 2016-05-29
From Joe:
Is it possible to build a barn roof (irregular pentagon?) with a 12' base and the other 4 sides 4' each? Thanks.
Answered by Penny Nom.
Placing a sphere in a cylinder of water 2016-05-27
From Fiona:
Hi the question i have is, if I have a cylinder filled with water and the volume of the water is 150Pi what would the rise in the level of the water be if you put a sphere into the cylinder with a volume of 500/3Pi? Sorry if it's a bit long winded
Answered by Penny Nom.
A cylinder in a cube 2016-05-25
From Sonia:
A cylinder has the same height and diameter as the sides of a cube use 3.14~ which has the greater volume
Answered by Penny Nom.
The area of a 4-sided lot 2016-05-25
From prasad:
How to find area of a land whose sides are 41ft,33ft,32.3ft and 33.2 ft. Pl give me the formula and proof.
Answered by Penny Nom.
Two pieces of rope 2016-05-21
From Render:
Fred cuts a 12- inch piece of rope. Then he cuts a second piece of rope that is 3/2 longer than the first piece. Is the second piece shorter or longer than the first piece? Explain.
Answered by Penny Nom.
A trough with a triangular cross section 2016-05-21
From Clarice:
A trough having an equilateral triangle end sections has sides equal to 0.4 m and 7m long.what is the volume of the liquid in the container if the depth of the water is one half the depth of the trough?
Answered by Penny Nom.
Euler's polyhedron formula 2016-05-20
From Antonia:
why does not cylinders follow Euler's polyhedron formula ( V-E+F=2) ?? if a cylinder has 3 faces, 2 edges and 0 vertices it doesn't follow Euler's formula???
Answered by Penny Nom.
The tens digit of a number is five times the unit digit 2016-05-19
From sanjeev:
The tens digit of a number is five times the unit digit. Find the number?
Answered by Penny Nom.
Filling a pit with glass pebbles 2016-05-17
From Sam:
I need to know how many pounds of glass pebbles are needed to fill a 24 inch across circular fire pit, if 5 pounds covers 4"H x 4"W x2"D? Thank u for any assistance, Sam
Answered by Penny Nom.
A puzzle embedded in a table top 2016-05-13
From Aaron:
I want to make a table with a puzzle embedded in it. The table top would be a 36" circle and the puzzle is 20"x27" I'm thinking that it's not going to fit, but not sure. Any help would be appreciated.
Thanks,
Aaron

Answered by Penny Nom.
The volume of a truncated rectangular pyramidal pond 2016-05-13
From Paul:
How do you calculate a partially filled truncated rectangular pyramid if you always know the bottom rectangle, the maximum height top rectangle perimeter, but have a varying height. Similar to filling up a pond you know the current height and dimensions at the max rectangle how do you calculate it half full i.e. 10x30 outside perimeter with a 2x8 base and a max height of 6ft how do you calculate it at 3ft without re-measuring the top perimeter. Thanks, Paul
Answered by Penny Nom.
A pair of equations with fractions 2016-05-11
From tiya:
hello, i want to know how to solve this question.

m/6+2n/3=6
-m/10=2n/5=2

Answered by Penny Nom.
A 70% off sale 2016-05-11
From virginia:
If the sale price is $129.99 @ 70% off - what was the original price?
Answered by Penny Nom.
At what time will Sara catch up with Jake? 2016-05-07
From Laura:
At 11:00 a.m., Jake started driving along a highway at constant speed of 50 miles per hour. A quarter of an hour later, Sara started driving along the same highway in the same direction as Jake at the constant speed of 65 miles per hour. At what time will Sara catch up with Jake?
Answered by Penny Nom.
A rectangular field 2016-05-07
From Jan:
A rectangular field is 63m long and 21m wide. A fence of 2m in height is needed to fence the field and fencing is also required to divide the field in three square sections. There are three wooden gates measuring at 1.5m to the three sections of the field. What is the total surface area of the fence needed for fencing and diving the field?
Answered by Penny Nom.
A 3 hour river cruise 2016-05-06
From Jan:
A 3 hour river cruise goes 15km upstream and then back again.The river has a current speed of 2km/h.what is the boat's speed and how long was the upstream journey?
Answered by Penny Nom.
A six digit code 2016-05-06
From Ralph:
How many combinations are possible if a "safe" has four buttons and you can use a six digit code? (these are just single press buttons..)For example, this could be one possible combination: Button 4 Button 1 Button 1 Button 3 Button 2 Button 4. Thanks!
Answered by Penny Nom.
Trigonometry 2016-04-30
From Joel:
I am bored with what I'm learning in 6th math class and want a challenge. I decided to look at trig. I couldn't find a good resource to teach me. Could someone either explain trig to me or show me a resource? Please don't say I'm too young to learn trig. I just am trying to learn.
Answered by Penny Nom.
Converting ml to g 2016-04-28
From Lerato:
I would like to know which formula should I use to convert ml to g?
Answered by Penny Nom.
A patio slab 2016-04-27
From Heaven:
Allie used 11.7m^3 of cement to make a square patio. If the thickness of the patio is 15 cm,what is the length of the patio?
Answered by Penny Nom.
Solve 2^2x + 3(2^x) - 4 = 0 2016-04-27
From Lloyd:
Solve the equation 2^2x + 3(2^x) - 4 = 0
Answered by Penny Nom.
Covering a site with 6 inches of rock 2016-04-26
From Carla:
if a pump house that measures 20'x16' sits in the middle of a site that is 50'x60' and you apply crushed rock to the site at depth of 6", how many yards will you need to haul?
Answered by Penny Nom.
One million is six percent of what number? 2016-04-26
From Colleen:
One million is six percent of what number?
Thanks!

Answered by Penny Nom.
Dimes and pennies 2016-04-26
From Renae:
Charity has 42 more pennies than dimes. Hope has 7 times as many pennies than dimes. Hope and Charity have the same number of dimes. Together they have $5.46. How many dimes and pennies do each have?
Answered by Penny Nom.
sin 2x - sin x = 0 2016-04-24
From lilly:
sin 2x - sin x = 0 0
Answered by Penny Nom.
The inverse function for f(x)=2x^2+5x 2016-04-23
From Ashini:
The inverse function for f(x)=2x^2+5x
Answered by Penny Nom.
A triangle inscribed in a circle 2016-04-22
From Olyana:
I am struggling with this question! Help!

So, there is a circle. In the circle, there is an equilateral triangle inscribed. Each side of the triangle is 20. There is no other info given, other than the triangle is inscribed in the circle and the sides of the triangle are 20. I am supposed to find the radius of the circle! Please help!

Answered by Penny Nom.
600(1+0.05)^7 2016-04-21
From chelsey:
I am unsure on how to solve this problem, 600(1+0.05) 7 ?
Answered by Penny Nom.
Two tax rates 2016-04-21
From Vishal:
Total amount paid annually $444 for 2014 which is inclusive for tax. tax rate for first six month is 7% then it is changed to 15% for second six months. calculate the total basic amount paid before tax.

the basic amount on which tax paid in first and second six month is same.

Answered by Penny Nom.
A sector of a circle 2016-04-21
From mustafa:
In a sector of a circle, the arc length is equal to half the perimeter of a sector.find the area of a sector in terms of r
Answered by Penny Nom.
15.86 acres 2016-04-21
From Ronald:
If a rectangular piece of land is 1320 ft. on one side, how many feet would be required on the other side to equal 15.86 acres?
Answered by Penny Nom.
A square of side length 4x-3 units 2016-04-20
From Bryan:
Find an expression that represents the area of a square with side length 4x-3
Answered by Penny Nom.
External and interior angles of a regular polygon 2016-04-19
From pearl:
a polygon has n sides.The exterior angle is 8 times the interior angle
find the value of the interior angle
find the value of n

Answered by Penny Nom.
The derivative of x! 2016-04-16
From Sang:
How to find the derivative of x! and integral of x!
Answered by Penny Nom.
Heights at various points along an arc 2016-04-15
From Isiah:
So I am working on a problem with a few friends; you have an arc with the center of its chord at 0,0. We also have a known sagitta and a known radius of curvature. How do we calculate the height extending in both the positive and negative directions?
Central sag: 2.48
Chord length: 9.6

Answered by Penny Nom.
Sloping my yard away from my house 2016-04-15
From Harold:
I need to slope a area of my yard away from my house and garage. The length of my house is 80 feet long and i need to slope it 22 feet away. I want to raise the dirt at the foundation by 6 inches and slope it down to nothing at the width of 22 feet. How much soil would i require?
Answered by Penny Nom.
A scale factor 2016-04-13
From tonya:
What is the scale factor for the two figures regular octagon with 15 and 9 written in decimal form
Answered by Penny Nom.
Mrs. Gibson has 3 children 2016-04-12
From MJ:
Mrs. Gibson has 3 children. The older ones are twins. The youngest one is 3 years younger than the twins. If the sum of their ages is 102, how old is the youngest one?
Answered by Penny Nom.
The area and the perimeter of a rectangle 2016-04-12
From kimberly:
is there a relationship between the are and the perimeter of a rectangle? explain.
Answered by Penny Nom.
tan15 2016-04-11
From JOHN:
find the exact value of tan15 in surd form.
Answered by Penny Nom.
The diagonal of a 10 acre square 2016-04-11
From Derrick:
I own 100 acre square of land. I want to run from farthest corner of property to farthest corner, Diagonally. How many miles would I have traveled?
Answered by Penny Nom.
Conversion of an equation 2016-04-11
From Marie:
How to you convert the equation of a line from x-intercept form (y=(x-x1)(x-x2)) to general form (y=ax^2+bx+c) if it involves square roots?

For example:
Convert this equation to general form: y=(x+the square root of 5)^2

Thanks for the help!

Answered by Penny Nom.
A road trip word problem 2016-04-10
From Marc:
While on a road trip I imagined this random word problem. Suppose I start a trip of 75 miles. My initial speed is 75 miles per hour. After every mile traveled I decrease my speed by one mile per hour. After the first mile I decrease my speed to 74 miles per hour and so on for each subsequent mile traveled. How long will it take to complete the 75 mile journey?
Answered by Penny Nom.
The area of a circle and a square 2016-04-10
From Richard:
I cannot understand why if you have a perimeter say of 4 units as the circumference of a circle then you reshape it into a square you lose very approximately some 20% of its volume but the perimeter length stays the same.
Can you please explain this to me as to why the volume decreases.

Answered by Penny Nom.
A stained glass cone lamp 2016-04-09
From Edwin:
In making a 16" dia. cone lamp (stained glass), how many square feet of glass do I need.
Answered by Penny Nom.
Setting up a pool 2016-04-09
From BETH:
i am trying to cover an area for a 15x15 foot round pool with play sand before I set up the pool. My playsand bag is 50 lbs , says it covers .5 cubic feet per bag. How many bags do I need?
Answered by Penny Nom.
Filling a hole with 14 tons of rock 2016-04-08
From Barry:
If I had 14 tons of inch and one half sized aggregate rock, how large of a square or rectangular shaped hole would I need to hold that amount?
Answered by Penny Nom.
4 carpenters can build 8 houses in 10 days. 2016-04-05
From Kenneth:
Hello:

Here is my question:

4 carpenters can build 8 houses in 10 days. 2 carpenters can build how many houses in 15 days?

Here is one solution:

The number of houses built is jointly proportional to the number of carpenters and the number of days. So h = kcd where k is a constant. Substituting the given: 8 = k*40, so k = 1/5. Our formula is then h = cd/5. I'm not sure how to determine whether or not one unit is jointly proportional to any other unit.

However, if 2 carpenters are unknown as in 4 carpenters can build 8 houses in 10 days. How many carpenters can build 6 houses in 15 days? What is the solution using this method? And likewise, if days are unknown, as in 4 carpenters can build 8 houses in 10 days. 2 carpenters can build 6 houses in how many days?

I thank you for your assistance.

Answered by Penny Nom.
Pizza delivery 2016-04-03
From Andrew:
Suppose you own a local pizza restaurant, Pizza with Pizzazz, and in order to compete with the big pizza chains in your area you are considering an advertising campaign offering customers a free pizza if their pizza is not delivered in 30 minutes or less. Even though your pizza restaurant is known for its fast and friendly delivery service, you are not sure if you can afford to give away too many pizzas for free. Looking over your past 12,421 pizza deliveries you find out 97% of the pizzas were delivered in 30 minutes or less.

Calculate the probability that all 100 randomly selected pizza deliveries will have been made in 30 minutes or less? Hint: Use the multiplication rule. (Round 4 decimals)

I'm really stumped on how exactly to do this problem. I don't need the answer just the steps broken down to show me how to get it! It would be gladly appreciated if you could help!

Answered by Penny Nom.
Maximizing the area of a two lot region 2016-04-03
From yousef:
A man wishes to enclose two separate lots with 300m of fencing. One lot is a square and the other a rectangle whose length is twice its width. Find the dimensions of each lot if the total area is to be a minimum.
Answered by Penny Nom.
The last two digits of a phone number 2016-04-03
From Joshua:
I want to find the last two digits of a phone number whose first eight numbers of a ten digit phone numbers are known.
Answered by Penny Nom.
20 mangoes 2016-04-01
From Mussharat:
I have 20 mangoes and have to put them in 5 boxes such that the numbers will be odd numbers.Also I can't cut or take the seed out from the mango . What should I do. It's really confusing.
I'll be more than happy if you could help me.

Answered by Penny Nom.
The volume of a cone 2016-03-31
From Odum:
Find the volume of a cone with radius 6.5cm and height 12.6cm
Answered by Penny Nom.
When does sqrt(x^2+y^2)=x+y? 2016-03-30
From Margret:
when does sqrt(x^2+y^2)=x+y
Answered by Penny Nom.
A tilted cylinder tank 2016-03-28
From Astri:
I have a problem determining the fluid level for tilted cylinder tank. Actually I've found some solution here for horizontal cylinder tank. What if the cylinder is tilted at a certain degree, for example 30 degree from the vertical axis.
Thank you.

Answered by Penny Nom.
The remainder theorem 2016-03-27
From Pratyasha:
A quadratic polynomial when divide by x+2 leaves a remainder of 1 and when divided by x-1 leaves a remainder of 4. What will be the remainder if it is divided by (x+2)(x-1)?
Answered by Penny Nom.
The volume of a box with a hexagonal base 2016-03-27
From Frank:
how many gallons of water in an 8" hexagon shaped box. 6" sides x 12.5" high ? The walls are 1" thick , beveled @ 30 degrees, so inside dimensions are 6"
Answered by Penny Nom.
A square based box and a cylinder 2016-03-26
From rajpal:
i m trying to calculate an area required to hold 4.4 mln cubic metres of volume. I used square and I get below result

A box shape that has dimensions 1500 meters (1.5km) by 1500 meters (1.5km) by 2 meters depth has a volume of:
= 4,500,000 cubic meters (4.5 mln cubic meters)

but when I use a cylinder shape, i get below result

A cylindrical shape that has a radius of 850 meters and a depth of 2 meters has a volume of:
= 4,539,600 cubic meters (4.54 mln cubic meters approx)

why is it that the cylinder, though of same depth holds more volume than a square? kindly clarify.

Answered by Penny Nom.
An isosceles triangle inscribed in a circle 2016-03-25
From NIHAL:
A isosceles triangle is inscribed in a circle having sides 20cm,20cm,30cm. find the radius of circle
Answered by Penny Nom.
Polynomial division 2016-03-25
From Ashley:
(4x-4+6x^3-x^2)/(3x-2)

The instructions say to "perform the division".

Answered by Penny Nom.
A problem in base x 2016-03-25
From Malith:
determine the value of base x of (211)x = (152)8

please mentioned the steps
Thank you

Answered by Penny Nom.
Travelling in a spacecraft 2016-03-25
From julie:
if i was travelling in a spacecraft at the speed of light and i turned on my headlight would i see the beam ?
Answered by Robert Dawson.
A rotating schedule for a softball team 2016-03-25
From Caroline:
I couldn't find a similar question, hopefully there isn't one!

I have a softball team of 18 people (7 girls and 11 boys), but am limiting each game to 13 players (6 girls and 7 boys). The season is 10 games long. How do I create a rotating schedule which allows members to play evenly? I tried separating the boys and girls to create rotation for each but I got confused. Some are unable to attend all games but for the simplicity of a rotation schedule can you please help?

Answered by Robert Dawson and Victoria West.
The inverse of a function 2016-03-20
From Billy:
f(x) = Square root(x^2 + 2x)

What is the inverse?

Answered by Penny Nom.
Biking and jogging 2016-03-17
From alondra:
Ricky went on a bike ride. After 6 miles he got a flat tire and had to jog home. He jogs 3mph slower than he bikes, so the jog took 1 hour longer than the bike ride. At what rate did he travel each way?
Answered by Penny Nom.
The perimeter of a rectangle 2016-03-17
From Linda:
Noel correctly adds the length of three sides of a rectangle and gets 88 cm her brother Ryan correctly adds the lengths of three sides of the same rectangle and gets 80cm. What is the number of cm in the perimeter of the rectangle
Answered by Penny Nom.
A block wall 2016-03-15
From Robert:
I have a wall 40 ft. long and 4 ft. tall as well as another one that is 30 ft by 3.5 ft. tall that I am trying to build. how many 6 inch by 12 inch landscaping blocks do I need?
Answered by Penny Nom.
The sides of a triangle 2016-03-15
From Hitarth:
Why we cannot construct a triangle ofngiven sides 5cm,5cm and 10cm?
Answered by Penny Nom.
tan inverse 1/4 2016-03-14
From nazz:
prove; tan inverse 1/4=1/3 cot inverse 52/47
Answered by Chris Fisher.
Angles 2016-03-12
From Laurynn:
What are angles in general (please include the 'angle of incline')

Thank you
Laurynn

Answered by Penny Nom.
The integral of a sum 2016-03-10
From Rahul:
How to solve definite integral of a sum. The specific problem is as follows,
Integral of ( 1+ sum of x^k, k=1 to k=n), x=0 to x=b *dx.
The answer is b + sum of b^(k)/k, k=2, to k=n+1. I understand only the integral of first term. But integral of the sum I do not understand at all.

Answered by Penny Nom.
A circle and a chord 2016-03-10
From Mujtaba:
The distance of a chord of length 16 cm, from the centre of the circle of diameter 20 cm
Answered by Penny Nom.
A word problem 2016-03-10
From Sam:
Jo is 10 cm taller than Ruth. Pam is 16cm taller than Ruth .Rod is 8cm taller than Pam. How much taller than Jo is Rod?
Answered by Penny Nom.
An equation with fractions 2016-03-09
From Ed:
7/10-___ +3/2=6/5
Answered by Penny Nom.
Can you construct a regular 21-gon? 2016-03-08
From Peter:
hi, i know that if i use a compass to draw a circle, i can use the same setting to mark 6 intervals along the circle circumference, how would i go about marking out 21 equally spaced points around the circumference?

if there an online calculator i can us, or some other interesting trick?

tia

peter

Answered by Robert Dawson.
Tiling a floor 2016-03-05
From joanne:
How many floor tiles 20x20 inch do I need for area of 8x 12 ft.?
Answered by Penny Nom.
The area of a rectangle 2016-03-03
From Lucas:
The area of a rectangle is given by A=x2+18x+72
-use factoring to find an expression for the dimensions of the rectangle.
-if the area of the rectangle is 7 square feet, what are the possible values of x?
-what are the dimensions of a rectangle?

Answered by Penny Nom.
A geometric progression 2016-03-03
From Pauline:
A woman measures the height of her child at birth and at monthly intervals afterwards.The child's height increases by 5% per month. Find the number of measurements she has made before the child's height is twice what it was at birth
Answered by Penny Nom.
Corrosion inhibitor in a pipeline 2016-03-02
From Edu:
I have a 12 in pipeline and 5 miles long. I need to coat it with corrosion inhibitor how much chemical will I need
Answered by Penny Nom.
Compressed Earth blocks 2016-03-02
From John:
how many 14"x10"x4" blocks do I need for a 1300sq foot house 8 foot high
Answered by Penny Nom.
A percentage problem 2016-03-02
From jehanzaib:
if x is a percentage: e.g. 40% than what does "x/(1+x)" = 29%. what is the explanation.
Answered by Penny Nom.
A rectangular prism 2016-03-02
From Paula:
Trying to help with a math problem. I don't know how to set up the equation for this.

A rectangular prism has a volume of 7.875m3rd and a height of 3.5 m. What is the area of the base of the prism?

Thanks for your help!

Answered by Penny Nom.
An algebra problem with a sphere 2016-02-29
From Sania:
If the number of square centimeters on the surface area of a sphere is equal to the number of cubic centimeters in its volume find its diameter
Answered by Penny Nom.
A deck that is half an ellipse 2016-02-28
From Steve:
On your website, I was reading a question and your response from a girl named Angela in which you provided a formula by which her father, a welder, could figure out points on an arc corresponding to equal 3' intervals on a 30' chord where the vertex was 1' off the chord. Is there an equivalent formula when working with an ellipse? I suspect this change will make the calculations significantly more complex. I am building a deck that is half an oval, and would like to be able to mark out the perimeter by measuring the distance from regular intervals on the primary access to a corresponding point on the perimeter. I will then connect the points on the perimeter and cut a reasonably smooth arc. The length of the primary access will be 22' and width of the deck at the vertex is 9'. I would like to be able to know the distance from the primary axis to a point on the perimeter at equal intervals of 6" along the primary axis. Can you help?
Answered by Penny Nom.
A 13 game bet 2016-02-28
From farah:
I'm trying to calculate the odds of a 13 game bet. Each game has 2 teams with 3 possible outcomes (win,draw,lose).

What are the odds.

Answered by Penny Nom.
10800 sq. ft equal approx what part of an acre? 2016-02-27
From David:
10800 sq. ft equal approx what part of an acre
Answered by Penny Nom.
A word problem 2016-02-27
From KRK:
amrutha thinks of a number, multiplies it by 5 & 6, devides the result by 3 and takes away the number first thought of to get an answer 36. find out the number
Answered by Penny Nom.
Solve for x and y 2016-02-27
From ntshidi:
Y=1/2x+4and1/4x-6
Answered by Penny Nom.
A place value drawing 2016-02-24
From Kristin:
Make a place value drawing of a number that has double the number of tens as ones and three times the number of thousands as hundreds write the number.
Answered by Penny Nom.
The sum of the angles of a triangle 2016-02-24
From Sophia:
Does every triangle add up to 180 degrees? (Such as a unique triangle)
Answered by Penny Nom.
The weight of some dirt 2016-02-24
From Michael:
How many tons of dirt are in a triangle 14M x10M x 8.1M x .8M deep?
Answered by Penny Nom.
Converting a fraction to a percentage 2016-02-22
From Preitty:
How can I turn fractions into percentages when the denominator is not a number that can multiply to 100?
Answered by Penny Nom.
How can I express Sin 4A in term of Sin A? 2016-02-22
From Odukoya:
How can I express Sin 4A in term of Sin A?
Answered by Penny Nom.
A bonus of 8% of sales 2016-02-22
From Barghavi:
A man earns $325 per week plus an additional 8% on any sales over $500. If he makes $6,250 in sales, how much money in total does he earn that week? thank you!
Answered by Penny Nom.
The evaluation of a 3 by 3 determinant 2016-02-19
From Kristen:
What is the step-by-step process on how to evaluate the determinant of a 3*3 matrix, using the expansion method (not the diagonal method)
Answered by Penny Nom.
The domain and range of a function 2016-02-19
From Genius:
State the domain and range g(x)=x(x-1)
Answered by Penny Nom.
The interior and external angles of a regular polygon 2016-02-17
From percy:
a regular polygon has n sides .The size of each interior angle is eight times the size of each exterior angle .
1.find the size of each exterior angle
2.calculate the value of n

Answered by Penny Nom.
Shooting a ball at a target 2016-02-16
From Thys:
Hi
I have a problem with the formula that i use .(for programming)
I have looked all over the web to find a solution but no luck.
I have a cannon that shoots a ball at a target
I use this formula to calculate what my initial velocity must be to hit the target at a angle of 30 degrees and a distance of 15m (the cannon and target position is known) It works perfectly if both is at same height but if one is higher or lower it miss.

In an example I am working with the range is 30m, the angle is 45 degrees and the target is 10m higher than my position.
Please help
Formula = V0 = √RG / Sin(2α)

Answered by Harley Weston.
0/0 2016-02-14
From Noni:
Q. 00=1 Why it is wrong when 44=1; 33=1; 22=1: 11=1 ?
Answered by Penny Nom.
Speed and velocity 2016-02-14
From kechi:
A boat sails south through Chesapeake Bay. It takes 10 hours to sail 110 kilometers. Describe the boat's motion. Calculate the boat's speed and velocity, showing the calculations. Explain how the boat's speed is different from its velocity
Answered by Penny Nom.
Perpendicular lines 2016-02-14
From Brendon:
points A (-4; 6) , B (1;-2), C (5;-3) and D (4; 1) are given prove that AC and BD are perpendicular to each other
Answered by Penny Nom.
Calendar arithmetic 2016-02-14
From Jenalee:
January 1, 2001 is Julian Day 2 451 911 (the number of days that have passed since Day 0, January 1, 4713 BC).

If Julian Day 0 was a Monday, what day of the week was January 1, 2001?

Answered by Victoria West.
Two equations in two unknowns 2016-02-13
From Anumba:
4x + 2y = 4
7x - y = -11

Answered by Penny Nom.
Todd is 3 years older than his brother Jack 2016-02-13
From Victoria:
Todd is 3 years older than his brother Jack. If Jack is x years old and Todd is y years old, write a rule that relates their ages over time. When Jack is 28 years old, how old will Todd be?
Answered by Penny Nom.
Travelling with and against he current 2016-02-09
From Lloyd:
A boat travelled 210 miles downstream and back. The trip downstream took 10hrs, the trip back took 70hrs
1. what is the speed of the current?
2. what is the speed of the boat in still water?

Answered by Penny Nom.
A 2 digit number 2016-02-08
From Lloyd:
The sum of digits of a certain 2 digit number is 7. Reversing its digits increases the number by 9. Find the number
Answered by Penny Nom.
Backfilling a rectangular hole for a shop foundation 2016-02-08
From Jeremy:
Hello, I'm going to be backfilling a rectangular hole for a shop foundation and need to know how much concrete and gravel I'm going to need to fill it in. The shop foundation is 38 feet wide by 30 feet long and 4 feet deep, there is also a concrete perimeter going inside the foundation that measures 16 inches wide and goes all the way around the inside of the foundation
Answered by Penny Nom.
The equation of a vertical line 2016-02-07
From Kagiso:
The equation for a vertical line that goes through the point (7; -3) is?
Answered by Penny Nom.
38 is what percent of 400? 2016-02-07
From chris:
38 is what percent of 400?
Answered by Penny Nom.
An exercise with factorials 2016-02-07
From vidhi:
find the value of n: (1-1/2) (2-2/3) (3-3/4)...(15-15/16) = n!/16
Answered by Penny Nom.
How many acres? 2016-02-06
From JOHN:
How many acres of land is in a strip that is 5000 foot long and 100 feet wide?
Answered by Penny Nom.
A metal gate 2016-02-06
From Carl:
I am a welder and I build gates. I have to put holes in a rail and then bend the rail in a curve. The problem is that the holes in the curved rail must line up with holes in the other straight rails. How do I calculate where to put the holes in the rail before I bend it? I will send a drawing if necessary.
Answered by Harley Weston.
The midpoints of the sides of a quadrilateral 2016-02-05
From Andrea:
The segments, joining, in order the midpoints of consecutive sides of a quadrilateral form a parallelogram.
Answered by Penny Nom.
When will Scott and Jill have earned the same amount? 2016-02-04
From kalia:
Scott starts with $10 and earns $5 and hour. Jill starts with $40 and earns $3 and hour. when will the two have the same amount of money in the same hours?
Answered by Penny Nom.
The height of a triangle 2016-02-03
From Brooklyn:
How do I figure out the height of a triangle when it only tells me the base of he triangle? And vice versa.
Answered by Penny Nom.
A two car competition 2016-02-02
From Christian:
Question: Two cars are racing to a fixed point and back. One car travels 70 MPH both ways While the other travels 60 MPH there and 80 MPH back, which car won the race? It is not a tie.
Answered by Penny Nom.
Division base 5 2016-02-01
From Jenalee:
I am having problems with a dividing bases question. I reviewed two that I could find in the database and tried the question as shown but I am still getting the wrong answer.

My question is 32\24043 to the base of 5 for both.

Answered by Penny Nom.
Golf for 6 - 2 three balls 2016-02-01
From Andy:
We are shortly having a golf holiday in Phoenix. There are 6 people playing 6 rounds, so we will play in 2 three balls. Is there a combination of pairings that ensures everyone plays with each other the same number of times. Many thanks for your help ! Andy
Answered by Victoria West.
Which term of the series 2+7+12+...is 152? 2016-02-01
From francis:
whice term of the series 2+7+12+...is 152?
Answered by Penny Nom.
Simplify 2016-02-01
From Sabira:
Simplify step by step
5x/8 + 7y/18 = 6

Answered by Penny Nom.
Subtraction in a base larger than ten 2016-01-31
From Jenalee:
Hello,

So happy I found this site. I am having problems with bases. My question is 97B9 - 6A3A base 16 for both.

Please help.

Answered by Penny Nom.
Percentage reduction 2016-01-30
From Kuuku:
The daily production targets in 2000 was 60,000 units this declined to 48,000 units in 2001 but was projected that further 300units reduction would be experienced in 2002. Calculate the percentage reduction by 2002.
Answered by Penny Nom.
Prove the earth is round 2016-01-30
From Kevin:
Working on a project for a science fair.
To prove the earth is round without the ability to get way above the surface.
How could we set up and experiment to see the curve.
My thought is using a telescope at the beach?
Form what we see so far the curve is 8 inches per mile?
So thought is set up a telescope and a target 1 mile away?

Answered by Robert Dawson and Chris Fisher.
A quadrilateral inside a square 2016-01-30
From Subrahmanya:
In a square ABCD of side 6 units P, Q are mid points of BC, CD respectively. The line segments BQ, DP intersect in R then find the area of the quadrilateral ABRD using only plane geometry.
Answered by Chris Fisher.
The diagonals of a polygon 2016-01-29
From Sofia:
What are diagonals and if you drew an octagon and drew all the diagonals how many would there be? Please explain because this is pretty confusing! Thank you!
Answered by Harley Weston.
Consecutive angles of a parallelogram 2016-01-28
From Hanna:
The consecutive angles of a parallelogram measures
Answered by Penny Nom.
Two increases of 20% 2016-01-27
From Z:
How do I find how many books are in a library given a problem like this... The number of books increase after buying 20% more in May. The number increased again by 20% after they were given 300 books. How many books did it start with?.
Answered by Penny Nom.
Two increases of 20% 2016-01-27
From Z:
How do I find how many books are in a library given a problem like this... The number of books increase after buying 20% more in May. The number increased again by 20% after they were given 300 books. How many books did it start with?.
Answered by Penny Nom.
Exponential form 2016-01-26
From Jufe:
What is the exponential form of √11x
Answered by Penny Nom.
A chord of a circle, the central angle and the radius 2016-01-26
From Nishan:
If chord length is given along with angle then how to calculate the radius.
Answered by Penny Nom.
Exponential growth 2016-01-26
From Paul:
The value of a stamp was 0.03 in 1851. The value in 2011 is $50,000. If the value increased exponentially, what is the annual growth rate?
Answered by Penny Nom.
I was paid 67% of the total owed 2016-01-25
From Julie:
I was paid $27000. This is 67% of the Total Owed. The Total Owed is unknown. How do I calculate the amount of the Total Owed?
Answered by Penny Nom.
The range of a function with a finite domain 2016-01-25
From Hannah:
Solve y=(1⁄4)x-1 if the domain is (-4,-2,0,2,4). I don't get how to do this. Can anyone help?
Answered by Penny Nom.
A system of linear equations 2016-01-24
From kareem:
my name is kareem
and i am a student i have a math puzzle and i tried to solved it but it always have same mistake
x-y=9
x+z=12
z-n=14
y+n=2

Answered by Penny Nom.
The diameter of the top of a truncated cone 2016-01-24
From Peter:
I am trying to calculate the diameter of a truncated cone given one diameter the height of the cone and a 10% taper from one end to the other. For example a butter churn is 18" tall and 9" in diameter at the base. the sides need to slope inward at 10%
What is the diameter at 9" and 18"

Answered by Penny Nom.
A quadratic equation with equal roots 2016-01-23
From abdiwahid:
X^2+2ax+4x+9a=0 is quadratic equation which has equal roots. Find the possible value of a?
Answered by Penny Nom.
Fractions of two quantities 2016-01-22
From Melody:
Kate ate 1/4 of her orange. Ben ate 2/4 of his banana. Did Kate and Ben eat 3/4 of theit fruit? Explain.
Answered by Penny Nom.
The length of an 80 acre piece of land 2016-01-21
From Eugene:
Have to clear a piece of land 80 acres by 500 feet wide. What is the length of the property?
Thanks Gene

Answered by Penny Nom.
Find two values of x satisfying f(x)=1 where f(x)=sin(ln(x)) 2016-01-21
From Ruth:
I'm trying to find two values of x satisfying f(x)=1 where f(x)=sin(ln(x))
Answered by Penny Nom.
The volume of a silo 2016-01-18
From Clinton:
Can you show me how to calculate the ground corn capacity in a steel silos of 10' x 10' high and 10' x 20' high and 10' x 24' high and 10' x 28' high
Answered by Penny Nom.
A Max/Min problem with an unknown constant 2016-01-17
From Guido:
Question:

The deflection D of a particular beam of length L is

D = 2x^4 - 5Lx^3 + 3L^2x^2

where x is the distance from one end of the beam. Find the value of x that yields the maximum deflection.

Answered by Penny Nom.
The perimeter of a square 2016-01-16
From dennis:
If I have eleven Square Acres, what would the perimeter dimensions be?
Answered by Penny Nom.
A limit of a rational function 2016-01-16
From selvamani:
F (x) = x^3+3x^2-9x-2 / x^3-x-6 and limit x tends to 2, f (x) exist then limit x tends to 2, f (x) is equal to ? How to answer this problem.
Answered by Penny Nom.
The perimeter of a one quarter acre square 2016-01-15
From Kerry:
If you have a perfect square that is one quarter of an acre what are the length of the sides and how do you arrive at the solution? thank you, Kerry.
Answered by Penny Nom.
Complex numbers in standard form 2016-01-15
From Michael:
express the following complex numbers in standard form (2+3i)+(5-2i)
Answered by Penny Nom.
Solve 1/3 ( x-5 ) + 4 =1/6 ( 2 - 3 x ) +1 for x 2016-01-15
From edwin:
1/3 ( x-5 ) + 4 =1/6 ( 2 - 3 x ) +1
Answered by Penny Nom.
A rectangular enclosure 2016-01-15
From Amber:
A rancher wants to use 300ft of fencing to enclose a rectangular area of 4400 square feet. What dimensions should the rectangle be?
Answered by Penny Nom.
Countable and uncountable sets? 2016-01-15
From wilson:
what are the countable and uncountable sets?
Answered by Penny Nom.
The range of a function defined piecewise 2016-01-13
From sarah:

f(x)={x-2, x<-2
       {x^2-4, -2_<x_<2
       {x+2, x>2

find the range
Answered by Penny Nom.

A triangular shaped garden 2016-01-13
From Demetrie:
Dwayne's garden is triangle-shaped with two equal sides and a third side that is 4 ft more than the length of an equal side. If the perimeter is 49 ft, how long is the longest side?
Answered by Penny Nom.
Sue's favourite number 2016-01-12
From Maria:
This is my son's homework. He is 7. Can you help?

Sue has a favourite number.
It is an even number.
It has 3 digits.
The digits add up to 15.

Find 10 numbers that could be Sue's number?

Answered by favourite number.
The perimeter of a triangular plot of land 2016-01-11
From Janelle:
I need to fence off 6.5 acres. The plot is triangular shape. How many feet would I be fencing off?
Answered by Penny Nom.
Three discounts 2016-01-10
From Tiffany:
Khairul wants to buy a sofa set. He is offered 3 successsive discounts of 10%,20% and 25%, and he can arrange them in any order he wants. Which order will benefit him the most? Explain your answer.
Answered by Penny Nom.
Water flowing through a rectangular drain 2016-01-08
From Tiffany:
the cross section of drain is a rectangle 30 cm wide. If water 3.5 cm deep flows through the drain at a rate of 22 cm/s, how many litres of water will flow through in one minute?
Answered by Penny Nom.
The area of a rectangle 2016-01-08
From ranjan:
if we make a rectangle with a 100cm of wire, then its area will be?
Answered by Penny Nom.
Integration of dx/(x^2+1)^3 2016-01-07
From Ishank:
Integration of dx/(x^2+1)^3
Answered by Penny Nom.
A pipe is installed with a 2% grade 2016-01-07
From peter:
a sewer ditches to be 148 feet long. the pipe is installed with a 2% grade. what would be total amount of fall be?
Answered by Penny Nom.
Three consecutive integers 2016-01-07
From ronn:
Three consecutive integers whose sum is 186
Answered by Penny Nom.
Two transport companies 2016-01-06
From Brynleigh:
The Sugar Sweet Company will choose from two companies to transport its sugar to market. The first company charges $5096 to rent trucks plus an additional fee of $200.75 for each ton of sugar. The second company charges $5500 to rent trucks plus an additional fee of $175.50 for each ton of sugar. For what amount of sugar do the two companies charge the same? What is the cost when the two companies charge the same?
Answered by Penny Nom.
A ratio word problem 2016-01-06
From Nina:
The length and the width of the rectangle is in the ration 5:3. Its area is 375m2. Find its perimeter.
Answered by Penny Nom.
A sequence 2016-01-05
From Mia:
the next three terms in each sequence. 0.4, 0.54, 0.68, 0.82,
Answered by Penny Nom.
A graph of the water level of a river 2016-01-05
From emoni:
Suppose that the water level of a river is 34 feet and that it is receding at a rate of 0.5 foot per day.
Answered by Penny Nom.
Four consecutive integers 2016-01-05
From sherica:
my teacher gave us an assignment and it says here that; THERE ARE FOUR CONSECUTIVE INTEGERS.IF THE SMALLEST ONE IS x ,FIND THE SUM OF THE FOUR INTEGERS. that is the question ...thanks hope that u can answer it
Answered by Penny Nom.
Find the quadratic equation whose roots are -4 and 7 2016-01-03
From sadiya:
Find the quadratic equation whose roots are -4 and 7
Answered by Penny Nom.
Markup as a dollar amount 2015-12-30
From Lori:
Hello,

I am trying to figure out mark up as a dollar amount. Is it the same as profit or is it a different number? And what is the formula to get to it, please? Thank you

Answered by Penny Nom.
The height of a parabolic arc 2015-12-30
From Tom:
Is there an algebraic means to determine the highest point of a parabolic arc if the base and perimeter are known?
Answered by Penny Nom.
Number of bricks needed 2015-12-30
From trudy:
if I have 250 sq ft of space that I want to fill with bricks that measure 7.5 in by 11.5 in how many bricks do I need to fill the 250 sq ft.
Answered by Penny Nom.
Book sales 2015-12-30
From Sandra:
Your finance text book sold 56,500 copies in its first year. The publishing company expects the sales to grow at a rate of 20.0 percent for the next three years, and by 8.0 percent in the fourth year. Calculate the total number of copies that the publisher expects to sell in year 3 and 4.
Answered by Penny Nom.
How can he raise his average to 90? 2015-12-29
From Raj:
Harris has an 87 in a class where daily works count 20%, quizzes count 20% and tests count 60%.
If there are only two test scores what must the score on his second test to raise his average to 90?

Answered by Penny Nom.
A relative maximum and a relative minimum 2015-12-28
From kemelo:
show for the following function f(x)=x+1/x has its min value greater than its max value
Answered by Penny Nom.
A circle is inscribed in a hexagon 2015-12-28
From Lalitesh:
A circle is inscribed in a regular hexagon ABCDEF
Prove that AB+CD+EF=BC+DE+FA

Answered by Penny Nom.
A troublesome word problem 2015-12-28
From Linda:
James is now 3/5 John's age. Three years ago, he was 1/2 John's age. Three years from now, he will be 2/3 John's age.
How old are they now?

Answered by Penny Nom.
Constructing simultaneous linear equations 2015-12-28
From Deborah:
Linda thinks of a two-digit number. The sum of the digits is 8. If she reverses the digits, the new number is 36 greater than her original number. What was Linda's original number?

Thank you!

Answered by Penny Nom.
Strings of characters 2015-12-28
From Ali:
If I have an app and offer a two, three and four digits name and it can be only number, letters or both?
I want to know how many options will I have for each?
For example
the two digits: aa, 11, a1 or 1a
the three digits: 111, a2a, 222
the four digits: 1111, 2ge3 or 1234
So if I used all the letters and all the numbers but nothing starts with a zero How can I calculate them separately? Or what's the result for each?
Thank you
Ali

Answered by Penny Nom.
A diameter of a circle 2015-12-27
From sahil:
Find the equation of diameter of circle x2 +y2-6x +2y-8 which passes through the origin.
Answered by Penny Nom.
Converting a fraction to a percent 2015-12-22
From Sharon:
How do you turn a fraction into a percentage? I'm beyond confused with this. Even though I think of myself as a good math student doing 8th grade math at a young age, this just makes me want to scream! I get the way you turn 1/4 into 25%, but when it comes to something like 7/9 = ? I just can't figure out the answer.
Answered by Penny Nom.
The angles of a triangle 2015-12-17
From Faith:
Does the measure of angle determine the length of its side? For example two angles are congruent then the sides are also congruent because from my understanding the angle determine the shape of triangle.
Answered by Penny Nom.
The perimeter of a 4 acre square 2015-12-16
From samantha:
What is the distance in miles or how many laps to make a mile, if one was walking around 4 acres of land which is like a square?
Answered by Penny Nom.
A bus trip 2015-12-15
From Michelle:
I do not know what equation(s) should be used in order to obtain the answer(s) to this word problem.

A bus was rented for a trip, the cost was dived equally amongst the passengers. During the trip, someone mentioned that if there were 9 more passengers, they would have paid each 5$ less. Another mentioned that if there were 6 less passengers, they would have each paid 5$ more. What is the cost of renting the bus and how much must each passenger pay.

Answered by Penny Nom.
Proof that an erroneous algebraic statement is false 2015-12-14
From Berteanu:
I need help with this proposition:
"It exists x a real number that for every y real number 5*x-2*y*y=1
This is false.
Let x be from R.
And I need an y real number that 5*x-2*y*y!=1
Please,could you help me?

Answered by Penny Nom.
Sierpinski Pyramid 2015-12-14
From victor:
Is a tetrix (a Sirpienski Pyramid/Tetrahedron) its own hyperplane?...alternatively, is it a hyperplane?
Answered by Robert Dawson.
The positive root of sin(x) = x^2 2015-12-13
From Kemboi:
Find the positive root of the equation sin(x) = x^2
Answered by Penny Nom.
Linear equations in two variables 2015-12-13
From priya:
I have problem in solving these equations please help me today itself very urgent:
I)2x+y=y
II)pie*x+y=9

Answered by Penny Nom.
The dimensions of a rectangle given its area and aspect ratio 2015-12-13
From colum:
Can you work out the length and width of a rectangle where you know only the area and aspect ratio
Answered by Penny Nom.
Constructing a cross country district schedule 2015-12-13
From David:
Retired math teacher trying to help son-in-law schedule a cross country district schedule. The would like to have four tri-meets each week for five weeks and one week of dual meets. The score the tri-meets as three duals, i.e. 1v2, 2v3, 1v3 constitutes one tri-meet. After many hours, not sure its possible, but I have forgotten a great deal! Thanks
Answered by Victoria West.
Building a dreamcatcher 2015-12-10
From Faye:
I have been asked to build a dreamcatcher, which is round into a 3x3foot area. What would the circumference be that I would need to make the hoop? I am thinking it is 9.42 feet long but am not good in math.
Answered by Penny Nom.
Matthew skateboards around the school 2015-12-09
From Abigail:
Matthew skateboards 4km each hour.
How long will it take him to skateboard around the school yard measuring 300m by 200m.? Thank you.

Answered by Penny Nom.
The line of intersection of two planes 2015-12-09
From Rabz:
Determine the vector equation for the intersection between the two given planes 2x+7y equal to 14,x+z equal to 7
Answered by Penny Nom.
The original price before a discount and taxes 2015-12-09
From Michelle:
Good day,

I would like to know if there is a particular equation to validate the following information:

I had to find the original cost of an item sold for 759.36$ before a 25% discount and 13% taxes. I know we must use separate question to obtain the answer but I am unsure how to write the equation to validate my answer.

Answered by Penny Nom.
20 golfers playing a 20 week season 2015-12-07
From Jeff:
We have 20 golfers playing a 20 week season. We play in foursomes. How best to set foursomes so everyone can play with every without playing with the same person multiple times?
Answered by Victoria West.
Travelling in opposite directions 2015-12-06
From Roselyn:
Jenny and Mark commute to work, travelling in opposite directions. Jenny leaves the house at 8 AM, and averages 35 kph. Mark leaves at 8:15 AM, and averages 40 kph.At what time will they be 40 kilometers apart?
Answered by Penny Nom.
Compacted and uncompacted soil 2015-12-05
From J.H.:
I am negotiating with a company to sell them land that they would use for excavating soil to be used in construction. I would like to value the land based on the volume of soil they are likely to remove. I have seen several answers, giving the calculation based on 43,650 sq. ft./acre x number of acres x number of feet in depth, divided by 27 to convert the number to cu. yds. However, that is the number when compacted. They pay $.50/yd. of soil removed, but that yd. is not compacted. How do you calculate the number of yds. of uncompacted soil in 1 acre of land?
Answered by Harley Weston.
A word problem with percentages 2015-12-05
From Caedryn:
After giving 25% of her stickers away, May had 50% as many stickers as Rose. If they had 200 stickers altogether at first, how many stickers did Rose have?
Answered by Penny Nom.
A schedule for a league with 15 teams 2015-12-05
From Zac:
Hello,

I have a league schedule question. We have a league where we have say have 15 teams. Each team is to play each other twice during a 10 week session.
However each team tries only to play 3 matches(teams) per night(week).
How would we set up a random schedule for the 10 week session?

Answered by Victoria West.
Drawing an arc 2015-12-04
From hassan:
how to draw a curve long 1m with an angle of 22.5?
Answered by Penny Nom.
The height of a truncated cone 2015-12-04
From Jack:
I need to build a truncated cone that has a top of30 inches and a base of 64 inches . The sides need to be at a 64.5 degree angle. This will determine the height. Can this be calculated?
Answered by Penny Nom.
A tangent line to a parabola 2015-12-02
From pei:
Given that the line y=mx-5 is a tangent to the curve y=2x^2+3 find the positive value of M.
Answered by Penny Nom.
Riding a mountain bike up and down a mountain 2015-12-02
From sam:
Michael, can climb a mountain at 2.5km/hr on his mountain bike. he descends the mountain at 5.5km/hr. he completes the whole circuit in 7 hours. how long is the trail to the top of the mountain?
Answered by Penny Nom.
A parabolic arch 2015-11-30
From Muhammad:
An arch over a road has a parabolic shape it is 6 meter wide at the base and is just tall enough to allow a truck 5 meter high and 4 meter wide to pass
a): assuming that the arch has an equation of the form y=a(x)^2+b use the given information to find a & b. explain why this assumption is reasonable.
b): sketch the graph of arch equation

Answered by Penny Nom.
Pouring a foundation 2015-11-27
From Lisa:
Hi im building a house 30ft long 18 ft wide I would like to pour a foundation of 6 inches deep. How much sand, cement , 1/2" gravel do i need.
Answered by Penny Nom.
The sweep angle of a video camera 2015-11-25
From Franc:
a television camera is 30ft from the sideline of a basketball court 94 ft long. The camera is located 7 ft from the mid court. through what angle must it sweep in order to cover all action on the court?
Answered by Penny Nom.
The angle at the vertex of an isosceles triangle 2015-11-25
From Karan:
I have been given an isosceles triangle. the Top angle is what i have to find out and the two sides adjacent to it are both 4.9 cm. i have been told that the area of the triangle is 4 cm^2. i have no idea how to work this out, any ideas?
Answered by Penny Nom.
The range of f(x)=(2x+2)/(x-1) 2015-11-25
From Nazrul:
f : R to R is a function which is defined by f(x)=(2x+2)/(x-1).
Is f(x) an onto function? Please explain.
What is the range of this function?
Thank you very much for your previous help.

Answered by Harley Weston.
How much does the Earth curve over a one foot distance? 2015-11-24
From Sean:
Hi, I am trying to figure out how much the earth curves over a one foot distance. I'd like to be able to draw the exact arc on a piece of paper. I am an artist and am looking to make glass vessels with the exact curvature of the earth. I read on your site that it curves approximately 8 inches per mile. can I just use simple ratios to break it down into inches?? Thank you so much for your help.
Answered by Harley Weston.
The measure of an angle in terms of its complement 2015-11-22
From Pam:
Can you please help me so I can help my daughter the equation is the measure of angle v is 4 time the measure of its complement what is the measure of angle v when the equation is 4x+x=90
Answered by Penny Nom.
Dividing by a fraction 2015-11-21
From Jennifer:

Question from Jennifer, a student:

I want to know how to get the right answer for this math problem, dividing a fraction in to a whole number , example 3/8 using the whole number 6? Thanks


Answered by Penny Nom.
20 million as a percentage of 7.3 billion 2015-11-18
From Nick:
Based on the estimate of the worlds current population (7.3 billion people), I'm trying to work out what percentage of that figure 20 million people would amount to?

(Apologies in advance that I've no idea if the 7.3 billion figure is an American Billion or UK billion)

Thanks for any help.

Nick.

Answered by Penny Nom.
Archimedes, Euclid and "Circular Reasoning" 2015-11-15
From Ron:
I have read about Archimedes and his work with sphere in cylinder and cone in cylinder and the volume relationships. Did he or any others also extend this to regular based polygon based regular like pillars, and columns? The ratio of 1/3 to 1 whole holds true with all regular based columns as example: a regular pyramid having a regular hexagon base inside a regular hexagon column of equal height.
Answered by Chris Fisher.
A common tangent to two general parabolas 2015-11-15
From Kind:
Hi, I want to find the common tangent of two general parabolas, but i don't know if it's possible or not.
If it's possible, please make a tutorial.

The first parabola equation : Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0.
The second parabola equation : Gx^2 + Hxy + Iy^2 + Jx + Ky + L = 0.

I need this because i want to find the equation of Beloch fold. (Huzita - Hatori 6th axiom) However if you know any other method to find Beloch folds equation, I am open for any suggestions.

Answered by Chris Fisher.
A schedule for 12 high school golf teams 2015-11-15
From Jason:
I have 12 high school golf teams (A - L). There will be 4 games each week for 4 weeks. For each game, 3 teams play at a time (A vs B vs C). I would like it where no team plays the same team twice. Week four is my issue as I seem to always have a team or two playing the same team again. Is it possible to have each team play each other only once?
Answered by Victoria West.
Dealing with surds 2015-11-14
From Agnes:
simplify (1-√3)(13+√3)
Answered by Penny Nom.
The diagonal of a rhombus 2015-11-14
From Om:
In a rhombus ABCD, angle A=60 and side AB=6 cm. Then diagonal BD is ?
Answered by Penny Nom.
The area of a domed roof 2015-11-13
From Brandon:
I have a tank with a 13' radius that has a domed roof of 3.5' tall How do I figure out the area in SQFT?
Answered by Penny Nom.
A three digit number 2015-11-13
From Tina:
The sum of the digits of a 3-digit odd number is 13. The digit in the tens place is 4 less than the digit in the hundreds place and 3 more than the ones digit. What is the number?
Answered by Penny Nom.
Working with fractions 2015-11-12
From muhammad:
There are 1200 pupils in a school, 2/3 of them are girls, 1/4 of the boys are overweight.How many boys are overweight?
Answered by Penny Nom.
A volume in cubic yards 2015-11-12
From James:
The first formula for figuring cubic yards of concrete need is length in feet, times width in feet, times depth in actual inches, divided by 320. Such as, 150x 50 feet x 4inches divided by 320 = cubic yards. How and why does this formula work?
Answered by Penny Nom.
A concrete container 2015-11-12
From Karstin:
The exterior of a concrete container will be 10 feet by 8 feet by 4 feet tall. The walls and the bottom are 6 inches thick. What will it cost to construct it if concrete is $98.95/cubic yard?
Answered by Penny Nom.
Fencing around a rectangular field 2015-11-11
From Darlene:
Question from Darlene, a parent: A farmer has 10,000 meters of fencing to use to create a rectangular field. He plans on using some of the fencing to divide the rectangular field into two plots of land by constructing a fence inside the rectangle that is parallel to one of the sides. Let X be the width of the rectangular field. Write an equation to express the area of the field as a function of X. Find the value of X that maximizes the area of the field.
Answered by Penny Nom.
Roof Square footage 2015-11-11
From Todd:

Question from Todd:

Good Day.
I have to figure out the square footage of a quonset style roof that's not playing by the rules The building dimensions (rectangular) are 63'x135' the height of the roof is 9.25'. It not an entire Quonset, It's that style of roof,(curved). There are concrete block walls 10' up to the metal roof.

Thank you!

Todd


Answered by Harley Weston.
The combination to a locker 2015-11-11
From Jason:
Hi,
I can't seem to open my locker cause I forgot the combination, the numbers are 1-8 Without repeat for 4 number for example 1234 or 2345 for numbers 1-8 without any repeat.

Answered by Harley Weston.
The derivative of x^1/3 2015-11-08
From omar:
hi can help me
am teacher ask me about x^1/3 Derivation definition .

Answered by Penny Nom.
Is 22/7 bigger or smaller than 3.14? 2015-11-06
From Natalie:
Is 22/7 bigger or smaller than 3.14?
Answered by Harley Weston.
A schedule for 8 golfers over 5 days 2015-11-04
From Ged:
Hope you can help with the following to save next years arguments ! Schedule for 8 golfers playing as pairs in 2 X 4 balls on 5 days. No player to pair same player more than once and to have played with each player In the 4 ball. Thanks.
Answered by Victoria West.
The domain of cos2x/(sinx-2) 2015-11-02
From Ameen:
Find the domain of:
f(x) = cos2x/(sinx-2)

Answered by Penny Nom.
Factoring a trinomial 2015-11-02
From Eric:
2v(squared) +11v +5
Answered by Penny Nom.
A quadratic equation with known roots 2015-11-01
From Awudu:
Given the roots of the quadratic equation ax^2+5x+c=0 are 5 and -2/3,find the values of a,b and c.
Answered by Penny Nom.
Doubling the area of a pamphlet 2015-10-31
From Mariam:
A pamphlet has the following dimensions: 4 cm by 6 cm If the area of the pamphlet is doubled, what will be the length of each side if sides can be integer values only?
Answered by Penny Nom.
A 15 team tournament 2015-10-28
From Joseph:
We have a 15 team tournament. Each team plays all other teams. We need a schedule were each game has a work team. Thus at each fields we have two teams playing and one working. All teams need to play each other and also be a work team. Any help would be appreciated!!
Answered by Victoria West.
An 8 Team Basketball League Schedule 2015-10-28
From Janice:
We have an eight team league that play at four time slots each week. It's a seven week season. How do we schedule so that each teams plays each other at least once?
Answered by Victoria West.
A trig identity 2015-10-28
From Gail:
verify sec(x) =cot(x)+tan(x)/csc(x), the csc(x) is under both the whole term cot(x) + tan(x)
Answered by Penny Nom.
A 4 by 7 array 2015-10-27
From star:
don breaks a 4x7 array into a 2x7 array and another array.what is the fact for don's second array
Answered by Penny Nom.
The uniqueness of the lub 2015-10-25
From Aishwarya:
Prove that if the lub and glb of a set exist then they are unique
Answered by Penny Nom.
An example of an irrational number 2015-10-22
From Allison:
It ask me to find an example of an irrational number less than -5 and I don't understand what the difference from a rational number and an irrational number besides the fact that a rational number can be repeated and shown in a simple fraction and an irrational number can't be written in a simple fraction.
Can you help me?

Answered by Penny Nom.
The sum of two repeating decimals 2015-10-22
From Kaitlin:
Here is the question I am struggling with:

Is the sum of two repeating decimals always repeating decimal? Explain your answer and give an example.

I answered this question thinking that no you cannot but only when adding 0.9 repeating, but my professor said this was incorrect.

Thanks for the help!
-Kaitlin

Answered by Penny Nom.
A schedule for a pool league 2015-10-21
From Hazel:
I have to make a schedule for my pool league. I have twenty teams each of which must play all other teams. I have ten tables which must also be rotated to all teams play on all tables.
Answered by Victoria West.
Subtraction in base 8 2015-10-21
From Adi:
Hi! Can you help me with a nagging problem, I searched a lot over the web and couldn't find it. I saw this site I gave it a try and I found it to my liking.

I am confused how to subtract bases from other bases:
567 (in base 8)
- 456 (in base 8)
______________
?????????
How do you do this? I do know how to carry and subtract with different bases. Can you please help me?

Thanks,
Adi

Answered by Penny Nom.
Simplify -3(x-7) 2015-10-21
From geraldine:
simplify: -3(x-7)
Answered by Penny Nom.
Scheduling a social curling league 2015-10-20
From Tyler:
I'm scheduling a social curling league where all skips will play with all thirds, all seconds, all leads. And all thirds will do the same and so on. We have 6 teams of 4 and will be doing 6 rotations. Is it possible that all skips will play with all other players from other positions without anyone doubling up?
My initial thoughts were (1,1,1,1) (2,2,2,2) (3,3,3,3) (4,4,4,4)(5,5,5,5)(6,6,6,6)... then rotate the thirds up and seconds down but don't know what to do with the leads and even with just 3 positions there's doubling (1,2,6,x)(2,3,5,x)(3,4,4,x)...4s have doubled (4,5,3,x)(5,6,2,x)(6,1,6,x) as you can see I'm having problems
If you could let me know if this is even possible it would be greatly appreciated

Answered by Victoria West.
6 teams randomly arranged in groups of 3 2015-10-19
From Anthony:
im trying to make a game scheduled for 6 teams using a 1vs2vs3 ; 4vs5vs6 format. all 6 teams randomly arranged in groups of 3. each team will play all teams at least twice, im trying to see how to make the number of times each team play another the same. schedule should be arranged as such 1vs2vs3 4vs5vs6 so that (1vs2, 1vs3, 2vs3) and (4vs5, 4vs6, 5vs6) i am limited to having only 2 sets of 3 at a time with 6 teams.
Answered by Victoria West.
An 8 team schedule 2015-10-19
From Dean:
I need an 8 team schedule for 2 time slots where 3 teams are on the ice per slot. I understand that there will be 2 teams on a bye per day. How do make sure that the byes are fair? Can you help me out?
Answered by Victoria West.
A six team league to play a 20 game schedule 2015-10-19
From Kelly:
Hi there. Some of your posts are close, but my problem is evening out the home and away games. We have 6 teams in our league and we are going to play a 20 game schedule, playing everyone 4 times. We will play Fridays and Saturdays, each weekend. Of course the ideal would be to have each team have a home and an away game each weekend, but I realize that is impossible, but I would like it as close as possible. Any help would be much appreciated!! We also were considering opening with a home and away - Friday then Saturday with the same teams. Then carrying on with playing everyone else and then possibly finishing up with the same home and home
Answered by Victoria West.
Acres of cattle waste 2015-10-19
From Chris:
In my first math problem, I found out that 100 cows will produce 21900 ft3 of waste over a year. However I don't know how to do the second part. How many acres of land would a farmer need to spread the waste on if he wanted it to be more that 6 inches deep? Thank you.
Answered by Penny Nom.
Six teams playing five games 2015-10-18
From Aidan:
I have six teams that will be playing five games.
I want each team to play each game once and each team to play each other team once.
Is this possible or should I add an extra round and let some teams play each other twice?

Answered by Victoria West.
Exponential form 2015-10-17
From Will:
What is exponential form of -8?
Answered by Penny Nom.
4 games in 4 time slots with 8 teams 2015-10-16
From Paul:
I'm trying to set up a game matrix for my kids that will have 4 games in 4 time slots with 8 teams. And every team is playing a different game in a different time slot. I provided the initial matrix and I am trying to ensure that no 2 teams play each other more than once. That's my problem.
8 pm 9 pm 10 pm 11 pm
Crokinole 1 vs 2
Trivial Pursuit 3 vs 4
Darts 5 vs 6
Pictionary 7 vs 8
Please help, I've been at it for hours.

Answered by Robert Dawson and Victoria West.
11 golfers over five rounds 2015-10-15
From Leo:
11 golfers over five rounds. Will golf as 4-4-3. How to set it up so everyone plays at least once with each player.
Answered by Victoria West.
The sequence 1,2,4,7,11,16... 2015-10-15
From HEMANT:
what is the next term in the sequence : 1,2,4,7,11,16,?
Answered by Penny Nom.
A schedule for 16 teams 2015-10-14
From Ellen:
I will have 16 teams. I would like to figure out how I can have 4 groups of 4 teams playing in hour increments, but never meeting more than once. How do I accomplish this? Thank you so much for any help you can give to me. .
Answered by Victoria West.
We are six golfers going away for 3 days of golf 2015-10-13
From Mike:
We are six golfers going away for 3 days golf. We are playing in 2 no threeballs playing concurrently. How can we arrange things so that everyone plays averydody else at least once. Is this possible.?
Answered by Victoria West.
The flight of a ping pong ball 2015-10-13
From Abigail:
Hello,

Wondering if there is a way to figure out the quadratic equation of half of a parabola?
Doing an assignment about finding quadratic equations for separate bounces of a ping pong ball, but the first bounce is incomplete (as the ball has presumably been dropped, hit the ground and then went on to make a complete bounce).
Please see attachment for references to the diagram that I am using.

Not sure whether I would have to look at it from a different perspective.

Thanks,

Abi

Answered by Harley Weston.
The area of two lots 2015-10-13
From Lynn:
I have 2 lots that have mobile homes on them... I was told they were 100 x 200 lots.. I have tried to calculate it on here but was not able to understand how to exactly do it. I would like to know if I have a 1/2 acreage or exactly what the 2 lots are?
Answered by Penny Nom.
2.236... 2015-10-13
From Ann:
2.236...
What is the most specific category of numbers does this fall into? Rational or Irrational? Does the .... mean that it repeats?

Answered by Harley Weston.
How can the probability be zero? 2015-10-13
From anagha:
Hi,
thank you for answering (beforehand)
The other day I was just thinking of circles and I came across this peculiar thing. Most of'em say that there are infinite number of points on the circumference. and, if it is true, if we spin the radius, the probability that it will point a a particular point is 1/infinity, right?
It didn't make any sense to me and so, I thought there might be an explanation or something of the kind...?

Answered by Harley Weston.
Mathematics 2015-10-13
From anagha:
Hi,
thank you for answering (beforehand)
The other day I was just thinking of circles and I came across this peculiar thing. Most of'em say that there are infinite number of points on the circumference. and, if it is true, if we spin the radius, the probability that it will point a a particular point is 1/infinity, right?
It didn't make any sense to me and so, I thought there might be an explanation or something of the kind...?

Answered by Harley Weston.
Squash scheduling 2015-10-01
From Ed:
I have 5 teams and 2 courts. Every Thursday we play at four different times (6,7,8,9 o clock)

Each team will play each other 5 times over 25 weeks.

Everyone should get to play evenly at the best time (6:00) and the worst time (9:00)

Answered by Victoria West.
I was wondering what xy means. 2015-09-30
From Eric:
I was wondering what xy means. My two things I think it means are the two digits of x and y or x times y. thanks for your time, Eric
Answered by Penny Nom.
sin(x/2)=cos(3x/2) 2015-09-27
From Valentine:
sin(x/2)=cos(3x/2)
I was trying to use cos3x=cos(2x+x) but there wasn't any progress

Answered by Penny Nom.
The length of a rectangle 2015-09-26
From Tris:
Hi,
I'm trying to figure out the length of a rectangle but i forgot how. So, the width is 5cm and the perimeter is 34cm.

Answered by Penny Nom.
The dimensions of a rectangle 2015-09-25
From Erick:
A rectangular strip of land has a perimeter of 124meters and an area of 385 square meters. Find its possible dimensions
Answered by Penny Nom.
2p^2+4p=16. How do i get p? 2015-09-22
From Dohie:
How do i solve this?

2p^2+4p=16. How do i get p?

Thanks

Answered by Penny Nom.
A 6-person team that has 9 players 2015-09-21
From Sheri:
I am organizing a 6-person team that has 9 players. How do I schedule them fairly over a 9 week league?
Answered by Victoria West.
A hockey roster of 19 kids 2015-09-21
From Brian:
We have a hockey roster of 19 kids. We only want to play 15 kids for each game. 4 players will not play each game. There are 16 games total. We want to rotate who doesn't play evenly. Can this be done? How many games will each player sit during the season?
Answered by Robert Dawson and Victoria West.
Square roots 2015-09-21
From mariana:
I have read various articles on how to find the square root of irrational numbers and every article out there seems to be very confusing.
i read you answer to LUKOW about irrational numbers and i am still quite confused. Say i want to find the square root of 326. i know that it is between 18 and 19 because 18 is the square root of 324 and 19 is the square root of 361 im just very confused about the rest of the process. Please help! ( if possible i would appreciate two examples. thanks)

Answered by Penny Nom.
32 golfers playing 6 rounds 2015-09-19
From scott:
i am looking for a schedule for 32 golfers to play 6 rounds and never play with the same person twice.
I made one for 28 golfers but i am struggling with 32.

Answered by Victoria West.
Partitions into distinct parts 2015-09-19
From Brian:
Looking for a formula where I can type in a number, 17 for example, and using the numbers 1 through 17 (1, 2, 3, 4 etc....), to come up with all possible combinations, when added, that will equal 17. And each number can only be used once. I've tried a few search engines but my computer stares at me blankly and scratches its head :-/.
Answered by Chris Fisher.
A word problem 2015-09-17
From Suszanne:
Multiplying a number by x yields the same result as dividing the number by 0.125. What is the value of x?
Answered by Penny Nom.
Two price reductions and a coupon 2015-09-16
From Suszanne:
Mary purchased an item for 45% off the original price, plus an additional 20% off the sale price.She also had a $5 off coupon, which the salesclerk applied after these two discounts. Mary's final purchase price for the item was $50. She paid no sales tax, what was the original price of the item?
Answered by Penny Nom.
Seven switches with 3 stages each 2015-09-15
From jeff:
We are trying to solve a combination problem. If I have 7 things that can be in 3 states (say on/partially on/off), and all 7 have to a state. How many different combinations can there be? It doesn't seem like we should treat it as 21 independent things, but not sure how to break the problem apart.
Answered by Penny Nom.
Order of operations 2015-09-12
From Tanisha:
I would just like to double check if something like 5x squared times 4x cubed equals 20x to the power of 5??
It's just that we were told you can only answer an equation like this if the base is the same...so does that mean the x part or the whole thing like 5x? I'm sorry if that didn't make sense!

Thank you for your help!!

Answered by Penny Nom.
20 golfers for 6 days 2015-09-11
From Dave:
have 20 golfers for 6 days. Each player should pair with 18 golfers used a system on your website which is good for 5 days, but cannot get the 6th day. Thanks for your help Dave
Answered by Victoria West.
18 golfers playing four rounds 2015-09-09
From Paul:
I have 18 golfers playing four rounds. I want two 3 balls and three 4 balls each day. I don't want anyone to play in a 3 ball more than once and I don't want anyone to play with the same person twice. I realise everybody can't play with everybody, I just want the best you can do.
Answered by Victoria West.
Scheduling for a bridge club 2015-09-09
From margot:
Can you help me with scheduling our bridge club?
8 rounds are played with four teams together.
There are 16 teams in total, so our schedule should look like eight 4x4 boxes.
(Each round the four teams play each other over the course of the evening)

Answered by Victoria West.
Division and units 2015-09-08
From Kenneth:
Hello:

Would there be a reason to divide a number without units by another number with units? Here is an example:

35 divided by $5.00 or 35/$5.00

The answer cannot have units ($) because $5 X 7 does not equal 35 but instead $35.00.

$35.00 divided by 5 or ($35.00/5) and $35 divided by $5.00 or ($35.00/$5.00) make more sense.

I thank you for your reply.

Answered by Robert Dawson.
An increase in savings 2015-09-06
From A student:
A man spends 80% of his income. His income increases by 40% and his expenditure also increases by 25%. Find the percentage increase in his savings?
Answered by Penny Nom.
HCF and LCM 2015-09-05
From Ally:
the HCF of the two numbers is 3, and the LCM is 15. what could the two numbers be?
Answered by Penny Nom.
A schedule for eight teams and four stations 2015-09-04
From Joel:
We are having a youth activity where we have eight teams and four stations. At each station there will be two teams competing against each other. We need each team to go through all four stations, but without ever competing against the same team, and, of course, without ever doing the same station twice.

If this possible? Thank you!

Answered by Victoria West.
A tangent line to a circle 2015-09-03
From Jamie:
Use the Greek method to find an equation of the tangent line to the circle x^2+y^2-4x+6y+4=0 at the points (3,2square root 2-3.
Answered by Penny Nom.
The weight of a pumpkin 2015-09-01
From Lisa:
A pumpkins weighs 10 pounds plus half of 10 pounds plus half it's own weight, what does the pumpkin weigh?
Answered by Penny Nom.
The diameter and circumference of a circle 2015-09-01
From Tracey:
Hello,
I own a custom workroom, I am figuring out fabric quantities or an estimate. When at the job site, I forgot to measure the diameter of the semi circle shape that I have to make a cushion for!!!
If the circumference of the semi circle is 165" what would the diameter be, maybe half this measurement????

I appreciate any help...I basically need the width from left to right to see if I can fit the cushion on one width of fabric that is 52" wide!

Answered by Penny Nom.
Three chickens weighed in pairs 2015-09-01
From Shelly:
My son brought home a problem of 3 chickens of different weights listing their weights in different groupings of 2. We are to determine the weight of all three together. I think it's a ratio problem, but I am too far removed to formulate a plan to teach him how to solve it.
Answered by Robert Dawson and Penny Nom.
Subtraction base 5 2015-08-29
From nakita:
can u explain the quinary subtraction ...
(3000) -(2342) all the numbers are in quinary number system

Answered by Penny Nom.
Working backwards 2015-08-27
From Heather:
Tom took a collection of tiles from a box. Sue took 13 and Bob took half of those remaining. Tom had 11 left. How many did they start with?
Answered by Penny Nom.
A schedule for an 8 person team 2015-08-27
From Julie:
We have 8 people on our team, but only 4 can play every week. We have 32 weeks, total. How can we divide this so everyone plays evenly ?
Answered by Robert Dawson.
A procedure for finding a square root 2015-08-27
From Tracey:
Is there a method/process to determine the square root of a large number?

For example, Tiananmen Square's area is 396 900m sq., what is the side length?


Thank you,
Tracey

Answered by Harley Weston.
Factor x^2 + y^2 2015-08-26
From Jerome:
Factor: x^2+y^2
Answered by Penny Nom.
A conditional probability problem 2015-08-24
From Faustina.:
Please I have an exam tomorrow. And I have tried by best in solving this Question. An urn contains 10 white, 5 yellow and 10 black marble. A marble is chosen at random from the urn and it is noted that it is one of the black marble, what is the probability that it is yellow?
Answered by Penny Nom.
Four equations in 3 unknowns 2015-08-23
From damien:
solve:
S x U - T = 44
T - U x S = 36
U + T - S = 7
U x U / S = 4

Answered by Penny Nom.
Reinforced steel mesh in a circular foundation 2015-08-22
From Padmesh:
in a circular foundation we are laying a reinforced steel mesh . i.e., like chords in both ways. the circle diameter is 2.91m and rods are placed 0.1m spacing. so I want to find the number of rods present in that circle. here by I am attaching an auto cad drawing for your reference
Answered by Penny Nom.
Arrangements of the letters STRANGE 2015-08-22
From Ravi:
In how many ways can the letters of the word STRANGE be arranged to that the vowels occupy only the old places.
Answered by Penny Nom.
A two digit number 2015-08-21
From Cameron:
Write the 2 digit number that matches the clues.

My number has a tens digit that is 8 more than the ones digit. Zero is not one of my digits.

My number is ________.

Answered by Penny Nom.
The distance over a Quonset 2015-08-20
From jane:
total base of hemisphere is 30 ft apex height is 20 feet what is total length over dome
Answered by Penny Nom.
A probability question 2015-08-19
From Omar:
Hi my name omar ,
I have an exam tomorrow and i want answer of this question
Thank you

Q:the probability distribution function of a discrete random variable X is given by
P(X=x)=kx^3
For X=0,1,2,3
a)the value of the constant k .

Answered by Penny Nom.
20 golfers playing four rounds 2015-08-17
From Paul:
I have a party of 20 golfers playing four rounds in fourballs. I realise that everyone will have 7 players that they do not play with, however I want to ensure that no one plays with the same person twice and that the Captain plays with the 12 players of his choice.
Answered by Victoria West.
Factor 2(x+1)(x-3)^2-3(x+1)^2(x-3) 2015-08-13
From Bella:
The directions are the solve and factor the expression completely: 2(x+1)(x-3)^2-3(x+1)^2(x-3)

I was factoring out an (x+1) and and (x-3) however the answer showing in my book is different and I can't figure out what I'm doing wrong please help

Answered by Penny Nom.
Parallelogram area 2015-08-04
From Nigel:
To find the area of a parallelogram you multiply the base by the height of the parallogram, the height being determined by an imaginary line drawn at right angles to the base. However if I made a parallelogram with joints at each corner and maipulated it to an upright position where the base and sides were at 90 degrees to each other,, I could then simply multiply the base times the height to get the area. Since the sloping side of the parallelogram does not vary in my imaginary jointed model, why can I not simply multiply the base by the sloping side to get the area in the same way that I multiply the base times the height of a square to find its area ? I cannot find the answer to this on the internet although I have searched.
Answered by Chris Fisher.
Rotating speakers through a 10 week schedule 2015-08-03
From Timothy:
I want 15 students to speak 7 times each over the course of 10 weeks.
They each will have 5 minutes.
Thanks

Answered by Victoria West.
An oil field barrel 2015-08-02
From Michael:
I have a storage tank that is 12' diameter x 22.5' high
it's capacity is 450 oil field barrels (42 gallon)
Which would hold 19,036 us gallons
I'm trying to find out how many inches it would take to make 1 barrel
I was able to get this far by using your volume calculator, but haven't been able to come up with the rest!
Thank you very much for your time, and I really appreciate this site and the tools you all have made available to everyone for free!
Hope to hear back from you soon and God bless you all!!

Answered by Penny Nom.
The length of a shadow 2015-08-01
From maaz:
Hello
I am having trouble with this question:

Lizzie, who is 6 feet tall, stands in her driveway at night, exactly 24 feet from the base of a spotlight, and casts a shadow that is 12 feet long if her friend Hannah who is 5 feet tall decides to stand next to lizzie how long will her shadow be?

Answered by Penny Nom.
The distance between two boats 2015-07-26
From mohammad:
Two boats leave the same dock at the same time,one traveling due east at 10 mph and the other due north at 24mph,how many miles apart are the boats after 3hours ?
Answered by Penny Nom.
Scale 2015-07-24
From Kenneth:

Hello:

Can you explain mathematically how the following scales become inches to feet?
For example, how does the scale of 1:160 become 1/16" = 1'?

(1:160) (1/16" = 1 foot) scale
(1:87) (1/8" = 1 foot) scale

I saw more of these different scale examples at the following:

http://www.oakridgehobbies.com/hobby-shop/modeling-in-scale-dimensions-f-a-q-s.html

I thank you for your reply!


Answered by Robert Dawson and Harley Weston.
Mary, Julie and Peter when on a trip 2015-07-10
From Edward:
How do you solve and set up a problem where: Mary pays one third of the cost of a trip, Julie paid half of what Mary paid, and Peter paid the remaining $75,
Answered by Penny Nom.
Golf for 12 with a proviso 2015-07-07
From Ken:
I hope you can help me. I'm trying to put together a draw for 12 players in 3 groups over 4 days. One proviso, 2 players must play together in each round because they require the use of a golf cart. We are due to play in September this year.
Thanking you in advance for any assistance you can give.

Answered by Victoria West.
The nth term 2015-07-04
From ujjal:
What is the nth term in the order 6,8,10....
Answered by Penny Nom.
Why is the area of square not conserved when it changes to a rhombus? 2015-06-28
From shubham:
Why is the area of square not conserved when it changes to a rhombus, both have equal sides still rhombus have less area than square.??
Answered by Penny Nom.
Why are bags of soil measured in litres? 2015-06-19
From Cheryl:
Why are bags of soil measured in litres?
Answered by Penny Nom.
My final exam score 2015-06-19
From Deirdre:
Hi,
I got 69% on a question worth 20%
68% on a question worth 20%


And the final exam was worth 60%

My final grade overall was 63%

Did I do very bad in the exam????

Answered by Penny Nom.
1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 x 0 + 1 = ? 2015-06-18
From Sharon:
1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 x 0 + 1 = ?

I got 1 as my answer despite BODMAS making it 12 because logic tells me I ought to place brackets around the first set of repeated addition. Could you please clarify this for me? Thank you 😊

Answered by Harley Weston.
4 digit strings using the digits 1, 2, 3 and 4 2015-06-14
From Gary:
What is the number of possible combinations using the following fact pattern?
A. Each combination must have 4 numbers.
B. The possible numbers to choose from are 1, 2, 3, 4
C. The numbers can be included in the combination more than once. For example, it can be 1111.

Is it possible to generate a schedule of the possibilities?

Answered by Penny Nom.
2^48 - 1 2015-06-13
From Soham:
The number 2^48-1 is divisible by two numbers between 60 and 70. The sum of the two numbers is?
Answered by Penny Nom.
A waste oil tank 2015-06-13
From Angela:
a waste oil tank is 5 feet wide and 20 feet long, the empty tank on your truck holds 5000 gallons. If 7.48 gallons are in every cubic foot, what is the maximum depth the oil can be to completely fit into your truck?
Answered by Penny Nom.
The amount before profit and overhead 2015-06-12
From kelly:
I have an existing amount of $22,750.00. this includes the profit at 10% and overhead at 10%. How do I remove the profit and overhead in order to come up with the original starting figure?
Answered by Penny Nom.
The area of an isosceles triangle 2015-06-11
From Pradipta:
Find the area of an isosceles triangle having two equal sides of 20 cm each and angle between them 45 degree ? ( solve without trigonometric function).
Answered by Chris Fisher.
A fantasy football league 2015-06-11
From Jason:
Hello. We have a fantasy football league with 14 teams. The season is 13 weeks long and we would like to figure out a way to have two divisions of seven teams each with each team playing their inter-division opponents twice. Is there a way to set this up? I cannot seem to find a way to do it. Thanks!
Answered by Victoria West.
8 golfers playing 5 round 2015-06-11
From Simon:
We have 8 golfers playing 5 rounds, and want to make the pairings as even as possible (ie all play against everyone else)

2 of the players however must play together each day - due to a buggy being required.

If anyone has a formula to work this out I'd be appreciated

Answered by Victoria West.
An equilateral triangle inscribed in a circle 2015-06-11
From Casey:
I have an equilateral triangle inscribed in a circle - this triangle has been bisected to give me 2 right triangles. I know the length of the line bisecting the equilateral triangle is 36 inches. How do I figure out the circumference of the circle and the length of the sides of the equilateral triangle?
Answered by Penny Nom.
Is 22/7 is an irrational number? 2015-06-07
From Sayak:
Is 22/7 is an irrational number
Answered by Penny Nom.
The surface area of a round bar 2015-06-06
From chirag:
Please tell me the formula for finding round bar surface in square inches/ mm
Answered by Penny Nom.
Manipulating an equation 2015-06-05
From Leigh:
Hi, I'm having trouble trying to find out how the equation y=mx+b for b comes up with the answer b=y-mx. Could you please assist me with this
Answered by Penny Nom.
A two digit number 2015-06-05
From Madison:
Trini took some photos. The number of photos she took is a two digit number. The sum of the digits is 11. The tens digit is 3 more than the ones digit. How many photos did Trini take?
Answered by Penny Nom.
The surface area of a triangular prism 2015-06-03
From Alex:
Find the surface area of a triangular prism with Isoceles triangles and dimensions 4 feet by 6 feet
Answered by Penny Nom.
The volume of a pipe 2015-06-02
From gordon:
What is the formula to find out how many gallon of water in a length of pipe tried your answer on 8inch at 50feet did not work out
Answered by Penny Nom.
A tangent to y = x^3 2015-05-31
From Brayden:
Show that a tangent line drawn to the curve y=x^3 at the point (d,f (d)), where d>0, forms a right triangle with the x and y axes in quadrant 4 whose area is (2/3)d^4.
Answered by Penny Nom.
A pentagon inscribed in a circle 2015-05-30
From Victoria:
find the area of a regular pentagon inscribed in a circle with radius 3 units
Answered by Penny Nom.
A stone walkway around a pool 2015-05-29
From Jerri:
I have a rectangular pool 15x30 and it will require stone placed around it 4 feet out and 4 inches deep how much will I need? Thanks, jerri
Answered by Penny Nom.
The perimeter of a rectangle 2015-05-28
From Imran:
The length of a rectangle is x+3 centimetres.
The width of the rectangle is x-1 centimetres.

Find an expression in terms of x for the perimeter of the rectangle.
The perimeter of a rectangle The perimeter of a rectangle
Give your expressions in it's simplest form.
The perimeter of a rectangle The perimeter of a rectangle
Thank You.

Answered by Penny Nom.
Two concentric circles 2015-05-28
From Shannan:
Two concentric circles have radii of 24cm and 26cm. What is the length of the chord that is tangent to the inner circle? Include a sketch
Answered by Penny Nom.
Prove that you cannot factor x squared + 5 2015-05-28
From lily:
the question is: prove that you cannot factor x squared + 5
Answered by Robert Dawson.
y=f(x) and y=-3/2f(x) 2015-05-27
From Kevin:
Could you please show me what change y=f(x) to y=-3/2f(x) has gone through and please graph.

y=f(x) points: (-3,0) ,(0,-2), (2,-2), (3,4)

how does (0,-2) change?

Answered by Penny Nom.
A path 30 feet wide by 2 miles long 2015-05-24
From Doug:
If I make a path 30 feet wide by 2 miles long how many acres am I covering?
Answered by Penny Nom.
The perimeter of a quarter circle 2015-05-21
From Bethany:
The perimeter of a quarter circle is 3.57. What is the quarter circle's radius?
Answered by Penny Nom.
Golf for 14: 2 fourballs and 2 threeballs 2015-05-20
From martin:
I have to organize 14 players to play four rounds of golf. Each round comprise two fourballs and two three balls .

What's the best combination to ensure that each persons plays with as many of the others as possible without playing with somebody more than twice?

Answered by Victoria West.
Manipulating an expression using logarithms 2015-05-18
From Katie:
Solve x=At^be^-ct for b in terms of c.
The e is Euler's number, not a letter or random placeholder.
v I've tried 2 methods on my calculator, and I am unsure as to why they give me different answers, and which one is correct.
For some reason, when placing a multiplication sign in between the A and the first t, I get a completely different answer. Why is this?
Also, which is the right answer for the question I have?
Thank you!
Katie :)

Answered by Penny Nom.
An isosceles right triangle 2015-05-17
From Ari:
In a 45-45-90 triangle find the ratio of a leg to the hypotenuse
Answered by Penny Nom.
Cubic feet and cubic yards 2015-05-17
From Richard:
If I have a bag that covers.8cubic ft how many bags are in 2.65 cubic yards?
Answered by Penny Nom.
An octagonal frame around a pool 2015-05-17
From James:
I have a 20' pool and need to put a frame around it using 2by 4 what r the lengths and angle cuts
Answered by Penny Nom.
The intersection of a plane and a cone 2015-05-16
From Tom:
Is there a way to derive an equation that describes the perimeter of the intersection of a plane and a cone regardless of the angle of the plane to the cone. Assume that the plane does not cut through the base of the cone, the x, y, z location of the vertex is known, the distance from the vertex to the plane through the axis is know., and that the angle of the cone is known.
Answered by Chris Fisher.
A pile of mulch 2015-05-15
From Justin:
I have a pile of mulch that measures 19 feet wide at the bottom and has a height of 6 feet. I need to know how many yards of mulch I have.
Please help and help with the formula for further use. Thank you!

Answered by Penny Nom.
Two lorries approaching an intersection 2015-05-15
From Nuraini:
Two straight roads intersect at the right angles. Lorry A, moving on one of the roads, Approaches the intersection at 50mi/h and lorry B, moving on the other roads, approaches the intersection at 20mi/h. At what rate is the distance between the lorry changing when A is 0.4 mile from the intersection and B is 0.3 mile from the intersection?
Answered by Penny Nom.
An angle of depression problem 2015-05-14
From haxir:
find the height of the balloon directly above a town if the measure of angle of depression of another town 5km from the first town is 20!6`
Answered by Penny Nom.
A calculus optimization problem 2015-05-14
From Ali:
Given an elliptical piece of cardboard defined by (x^2)/4 + (y^2)/4 = 1. How much of the cardboard is wasted after the largest rectangle (that can be inscribed inside the ellipse) is cut out?
Answered by Robert Dawson.
Folding a rectangle to preserve the aspect ratio 2015-05-09
From Anna:
If you fold a rectangular piece of paper in half and the resulting rectangles have the same aspect ratio as the original rectangle, then what is the aspect ratio of the rectangles?
Answered by Penny Nom.
Repeated decimals 2015-05-09
From Vir:
Years ago I (re?)discovered 'cyclic division'. For example: if you arrange the number along a circle and put the number 142857 at the centre all the numbers taken cyclically, starting with 1, are fully divisible by 37. Whatever the starting point of this number, it remains fully divisible by 37. what is more, the number can be formed by taking the digits clockwise as well as anti-clockwise..This I call "full cyclic divisibility". In many cases, only clockwise cyclic divisibility is possible. But I have not come across a case where ONLY anti-clockwise divisibility occurs. Thus clockwise cyclic divisibility seems to be favoured. Could this be construed as a sign of chirality in mathematics?..
Answered by Chris Fisher.
A word problem 2015-05-08
From JAMES:
A businessman bought a number of similar articles for a total of sh. 6000. Three of the articles turned out to be defective with no resale value. He sold the remaining articles at 12.5% each above the cost price making a total profit of sh 480. How many articles had he bought?
Answered by Penny Nom.
A triangle inscribed in a circle 2015-05-07
From R2D2:
A triangle is inscribed in a circle of radius 10. If two angles are 70 degrees and 50 degrees find the length of the side opposite the third angle?
Answered by Chris Fisher.
A circle is tangent to the y-axis 2015-05-06
From Elynna:
What does it mean when a circle is tangent to the y-axis?

Thanks,

Answered by Penny Nom.
Sales tax 2015-05-05
From Adalyn:
Hello i've been having some trouble with math, The question is asking for a GST and a PST of a 30.00 dollar shirt. I don't know how to find the GST or the PST please help
Answered by Penny Nom.
The surface area of a hemisphere 2015-05-05
From Mandy:
How can I show that the total surface are of any solid hemisphere is 75% of the area of the full sphere?
Answered by Penny Nom.
The number of possible musical notes using an n-key instrument 2015-05-04
From Farihin:
Lets say that i have keys, and each key is for notes of a musical instrument, So i wanted to find out the number of notes i can get for a certain number keys, of course in the form of an equation. Notes can use as many keys, it can use 1, or 2, or 3, or even 100.
Notes in real life is not as such, but ignore reality. I tried doing this but i can't seem to find a formula for it. For example, i have 4 keys, say A, B, C, and D. so, for notes that uses one key are 4, which is A, B, C, and D themselves. for notes that uses two keys are 6,
AB, AC, AD, BC, BD and CD.
for notes that uses three keys are 4,
ABC, ABD, ACD and BCD.
lastly for notes that uses all four keys is 1, ABCD.
So, the total will be 4+6+4+1=15#

The nth term for the first equation is n, the second is [(n^2)-n]/2 the third and the fourth, i don't know but the final answer should be like,
n + [(n^2)-n]/2 + [3rd] + [4th]

Sorry for the long question though...

Answered by Penny Nom.
13 games, 3 possible outcomes 2015-05-01
From Kennedy:
Hello, hope it finds you well.
Am not that good with numbers, can you please help me get all the possible outcomes of 13 games, with a home win, draw or an away win as three possible results for each of the 13 games.

Thanks in advance

Answered by Penny Nom.
The method of elimination 2015-05-01
From oreanna:

Question from oreanna, a student:

How do u solve 2x+9y=3

7x-4y=-25 in elimination


Answered by Penny Nom.
A square and a rectangle 2015-05-01
From nick:
why is the area of a square of a given circumference greater than the area of a rectangle with the same circumference ?
Answered by Penny Nom.
Filling a pool with dirt 2015-05-01
From Mike:
I have a hole which a 24 ft pool in it is 10" deep in the the centre and goes to 1" inch at the edge want to fill it in with dirt how many yards of dirt would I need to fill it in
Answered by Penny Nom.
The volume of a sphere 2015-04-30
From Cassidy:
How do you find the radius of a sphere that has volume 36pI?
Answered by Penny Nom.
A fraction with a negative exponent in the denominator 2015-04-30
From ellen:
7/ab to the -4 power
Answered by Penny Nom.
The volume of a cube 2015-04-30
From megan:
What's the volume of a cube with a side length of 6?
Answered by Penny Nom.
The surface area of a cut pipe 2015-04-27
From ARUN:
dear Sir,

please advise me , how to calculate the surface area of a pipe with diameter of 630 mm and thickness of 67 mm which is cut in a angle of 22.5 degree.

please show me how to calculate the surface area of the pipe which cut in an angle.

Thanking you.

Answered by Harley Weston.
A five-digit pass code 2015-04-25
From Mary:

Question from Mary:

More on your published question:

I have the same type of lock, but set up a 5-digit pass code. Is that more or fewer possibilities than a 4-digit code. How many digits would make the lock most secure? I don't believe Werner specified this, but each number can only be used once. Thanks, Mary


Answered by Penny Nom.
A piecewise function 2015-04-25
From uday:

f(x)={x^2+3x+2 / x+2, x(not equal to)=-1
{4, x=-1
how to find domain and how the graph looks like


Answered by Penny Nom.
Locating the center of a circle that forms an arc 2015-04-23
From Ken:

Find the Cartesian coordinates of the center of an arc with the given location of the beginning and end points and radius length. Not the midpoint of the circumference but the actual point that the arc
is drawn around.

I know their are two answers depending on the direction of the arc. Unless we assume that all arcs are drawn counter clock wise.

Thanks
Ken


Answered by Harley Weston.
A word problem with fractions 2015-04-23
From Cecilia:
if one third of a pole is red, one quarter is white and 15m is black what is the height of the entire pole
Answered by Penny Nom.
Expand and Simplify (3x+5)(5x-9) 2015-04-23
From chloe:
Expand and Simplify (3x+5)(5x-9)
Answered by Penny Nom.
Two concentric circles 2015-04-21
From Juniper:
Two concentric circles have radii of 4 cm and 8 cm. A segment is drawn so that it is tangent to the smaller circle and a chord of the larger circle. How long is the segment?
Answered by Penny Nom.
A circle inscribed in a square 2015-04-19
From michael:
A circle is drawn in a square PQRS. If the total area of the shaded portion of the square is 42 cm square, calculate the radius of the circle
Answered by Penny Nom.
A geometric sequence 2015-04-19
From Delfina:
In a geometric sequence the second term is 15 and the fifth term is -405. Find the sum of the first eight terms
Answered by Penny Nom.
An inequality 2015-04-19
From mr.:
Simplify the inequality √x>x and represent on a number line
Answered by Penny Nom.
A wireless fence 2015-04-18
From Dave:
I'm buying a wireless fence to keep my pet in my yard. It has a half acre range. In a straight line how far would that be?
Answered by Penny Nom.
Two cars approaching an intersection 2015-04-16
From Engabu:
Car A is traveling west at 50km/h & car B is traveling north at 60km/h. both are headed for the intersection of the two roads. At what rate are the cars approaching each other when car A is 3km & car B is 4km from the intersection?
Answered by Penny Nom.
How many boats total are in the marina? 2015-04-15
From Carla:
In a marina, 3/4 of the boats are white, of the remainder 4/7 are blue, the rest are red. There are 9 red boats. How many boats total are in the marina? My answer is 84 because if 1/4 of the boats are divided into sevenths, that makes the whole marina a 28 part item. 3/28 are red so 84 is the total number of boats. My child thinks I am wrong.
Answered by Penny Nom.
Two airplanes 2015-04-14
From john:
two planes leave an airport at the same time, one going northwest (N35*W)at 400 mph and the other going east at 332 mph. How far apart are the planes after 4 hours to the nearest mile?
Answered by Penny Nom.
Constructing a box of maximum volume 2015-04-14
From Margot:
I need to do a PA for maths and I'm a bit stuck. The PA is about folding a box with a volume that is as big as possible. The first few questions where really easy but then this one came up.

8. Prove by differentiating that the formula at 7 does indeed give you the maximum volume for each value of z.

Answered by Penny Nom.
Team selection 2015-04-13
From Peter:
I manage a football team with a list of 28 players.
Only 24 can play each game.
The season is 16 games.
How do I fairly select 24 players each week.

Answered by Robert Dawson.
Some non-decreasing sequences 2015-04-13
From Sky:
Hi I'm a Student and i'll try my best to state the problem perfectly.

The number of non-decreasing sequences of size at least 1 and at most N, such that each element of the sequence lies between L and R, both inclusive.

Eg:- N=1 L=4 R=5
ans= 2. [{4},{5}]

N=3 L=4 R=6
ans= 19. [{4},{5},{6},{4,4},{4,5},{4,6},{5,5},{5,6},{6,6} {4,4,4},{4,4,5},{4,4,6},{4,5,5},{4,5,6},{4,6,6},{5,5,5},{5,5,6},{5,6,6} ,{6,6,6}]

Answered by Claude Tardif.
The area of a circle given the circumference 2015-04-12
From F:
How do you find the area of a circumference of 6?
Thanks.

Answered by Penny Nom.
Excavating a basement 2015-04-12
From Randy:
The cost of excavation is $4.50/ cu yd. Find the cost of excavating a basement 87 ft long, 42 ft wide, and 8 ft deep.
Answered by Penny Nom.
Sharing $600 in the ratio of 2 to 3 2015-04-11
From Kenneth:
Hello:

If two people share $600.00 in a ratio of 2 to 3, which calculations are correct: 2/3 X $600.00 & 1/3 X $600.00 or 2/5 X $600.00 & 3/5 X $600.00?

The denominator 5 is determined by adding 2 and 3 from the ratio.

I thank you for your reply.

Answered by Penny Nom.
An 8 pointed star inscribed in a circle 2015-04-10
From Kermit:
How do you find the area of the star that is formed by two squares and surrounded by a circle. The only given information is that the radius of the circle is 10.
Answered by Penny Nom.
The perimeter of a quarter circle 2015-04-10
From Riley:
How do you find the perimeter of a quarter circle when the radius is 56?
Answered by Penny Nom.
A word problem with fractions 2015-04-09
From Lorraine:
If the numerator of a certain fraction is doubled and the denominator is increased by 1, the fraction becomes 1/2.

If the numerator of the original faction is squared and the denominator is decreased by 2, the fraction becomes equal to 1.

Let x be the numerator and let y be the denominator of the original fraction. Write down two simultaneous equation in x and y.

Solve these equations to find two possible values for the given fraction.

Answered by Penny Nom.
The area of the ring between two concentric circles 2015-04-08
From Conner:
The area of the ring between two concentric circles is 25pi/2 square inches. The length of a chord of the larger circle tangent to the smaller circle is?
Answered by Robert Dawson.
A circle graph 2015-04-06
From Davis:
i don't know how to answer this question. please help!

a survey about student government shows the following results

110 like the program
120 think the program is unnecessary
210 plan on running for student government next year

if this information is put in a circle graph,what is the central angle for the students who like the program?

Answered by Penny Nom.
On what day of the week did 1994 begin? 2015-04-05
From tayyaba:
there were 365 days in the year 1993 the first day of the year was friday. on what day of the week did 1994 begin?
Answered by Penny Nom.
A tangent to y=x^3 passes through (0,2) 2015-04-05
From Kevin:
Given that the curve y=x^3 has a tangent line that passes through point (0,2). Find the equation of the tangent line
Answered by Penny Nom.
The weight of a steel block 2015-04-04
From Mark:
the weight of a steel cube 37 inches X 28 inches X 7 inches
Answered by Penny Nom.
n^2 is a multiple of 100 2015-03-30
From Rahul:
I have to prove that n^2 is a multiple of 100 is necessary or Sufficient condition (or both) for n being multiple of 10
Answered by Penny Nom.
The game of 24 2015-03-28
From Suzanne:
I love this game! Cannot figure out 4,9,10,16 to equal 24? Help!
Answered by Penny Nom and Claude Tardif.
Three consecutive integers 2015-03-28
From Aleksey:
I need help how do I find the second of three consecutive integers if the sum of the first and third is 26?
Answered by Penny Nom.
Ordering fractions 2015-03-27
From latoya:
Put the following amounts in order from greatest to least 60%,2/3,0.599 explain answer
Answered by Penny Nom.
A rectangular concrete tank 2015-03-24
From mwenge:
What is the length ,width and height for the rectangular concrete tank that can have capacity of 50000 liters of water?
Answered by Penny Nom.
Is a rhombus a square? 2015-03-24
From Justin:
Is a rhombus a square?
Answered by Penny Nom.
Dealing cards to Melissa and Robert 2015-03-24
From Karena:
92 cards in all. Melissa has 3 times as many cards as Robert. How many cards does Robert have?
Answered by Penny Nom.
An isosceles triangle inscribed in a circle 2015-03-23
From Rachel:
Triangle ABC is an isosceles triangle inscribed in circle O. If each leg of the triangle is 13cm and the altitude to the base of triangle ABC is 5cm, find the radius of the circle.
Answered by Penny Nom.
A train trip 2015-03-23
From Ngcebo:
A train travels a distance of 720 km at a speed of x km/h. on the return journey, it travels at an average speed of y km/h and completes the whole journey in an hour less. if the speed during the return journey was 10 km/h more, what were the speeds in m/s
Answered by Penny Nom.
16 golfers for 18 weeks 2015-03-22
From Rose:
We could use a schedule to include the following:
16 golfers
4 foursomes
Each person plays once a week for 18 weeks.
No one plays in same foursome more than 1 or 2 times, or the least amount of time.

Thank you for your kindness.

Answered by Victoria West.
8 golfers playing in 2x2 balls in 5 games 2015-03-18
From Brian:
We are 8 golfers who will be playing in 2x2 balls in 5 games. is there a formula to minimize the chances of playing with a partner or opponent too often please ?
Answered by Victoria West.
The weight of two dogs 2015-03-17
From Renee:
Darlene's dog weighed 5 times as much as Leah's dog. Together, the dogs weighed 84 pounds. How much did each dog weigh? Write an equation and solve
Answered by Penny Nom.
A region defined by three lines 2015-03-16
From Lucinda:
find the area of the figure formed by the line y=-5x+9 and the x-axis and y-axis.
Answered by Penny Nom.
A cone of maximum volume 2015-03-16
From Mary:
I have to use a 8 1/2 inch by 11 inch piece of paper to make a cone that will hold the maximum amount of ice cream possible by only filling it to the top of the cone. I am then supposed to write a function for the volume of my cone and use my graphing calculator to determine the radius and height of the circle. I am so confused, and other than being able to cut the paper into the circle, I do not know where to start. Thank you for your help! -Mary
Answered by Robert Dawson.
Points on the x-axis 2015-03-14
From Justin:
jamie tells her friend that ordered pairs that have an x-coordinate of O line x-axis. She used the origin as an example. Describe Janine error. Use a counterexample to explain why Janine statement is false
Answered by Penny Nom.
Two-tiered GST system 2015-03-14
From Ruby:
This question showed up in one of my Math assignments and nothing on the internet seemed to help me find a way to calculate it.

A certain country has a two-tiered GST system. For the first $1500 of any item, GST is levied at 10% and any amount over $1500 is levied at 15%. Determine the amounts that give the following GSTs.
a) $350
b) $780

Answered by Penny Nom.
Average rate for a return trip 2015-03-14
From Michael:
Jeffrey drove to a town 25 miles away at an average speed of 50 miles per hour. The return trip along the same route took 20 minutes longer than the trip to town. Determine the average speed in miles per hour for Jeffrey's round trip.
Answered by Penny Nom.
The side length of a gazebo 2015-03-14
From Dennie:
From middle of side to middle of opposite is 14'6". What is the length of the side?
Answered by Penny Nom.
A limit 2015-03-13
From arthur:
sin(x-1)/x^+x-2
Answered by Penny Nom.
Commission 2015-03-13
From Rose:
A shopkeeper receives 12.5% (12 1/2 %) commission on the sale of books from the publisher. In a certain month,he receives a commission of rs.250 from the publisher. How much was his sale for that particular month??
Answered by Penny Nom.
A fishfinder 2015-03-13
From Dave:
I have a fishfinder that has a 20 degree cone on bottom of boat going to the bottom of the lake. How do I know the size of base diameter of the cone on the lake bottom depending on depth... such as 10 feet deep, for example?
Answered by Penny Nom.
Olivia and Ray walk to school 2015-03-12
From Rebeccah:
Olivia and Ray walk to school. Olivia walks 1/4 of a mile to school. Her walk is 2/3 of the distance that walks Ray to school. What is the total distance,in miles,that Ray walks to school?
Answered by Penny Nom.
Two sunflowers 2015-03-12
From Maurice:
Sam and sally planted two sunflowers.Each sunflower grows 1cm each day. Sally's sunflower is 4cm high. Sam's is 12cm high. How high will each sunflower be when Sam's sunflower is twice the height of Sally's?
Answered by Penny Nom.
Constructing a cone 2015-03-12
From Levi:
While the mathematics at the welding shop page was very helpful there is one vital part missing. If I have never built a cone how do I figure out how much bigger the diameter of my circle has to be when laying flat on the floor verses the diameter when it has been pulled into a cone.
Answered by Harley Weston.
The height of an equilateral triangle 2015-03-12
From anna:
I am anna and i am in 7th grade.
i am trying to find the height of and equilateral triangle, all sides equaling 4 inches

Answered by Penny Nom.
The volume of a trench 2015-03-11
From Kim:
A trench 60m long and 15m deep, 12m wide at the top and 8m wide at the bottom.How many cubic meters of earth have been removed?
Answered by Penny Nom.
The area of a quadrilateral 2015-03-11
From Joel:
Diagonal ac of quadrilateral ABCD is 60cm and the lengths of perpendiculars to It from the opposite vertices are 4.2cm and 5.8 cm find the area of the quadrilateral ABCD
Answered by Penny Nom.
What is 1000 billion billion? 2015-03-10
From LeRoy:
what does this mean? 1000 billion billion
Answered by Penny Nom.
Two consecutive odd integers 2015-03-09
From gowtham:
The sum of two consecutive odd integers is 20.find the integers
Answered by Penny Nom.
Angles of elevation and depression 2015-03-08
From Timmy:
Joel is walking down a street and sees a 115 ft tall building in front of him. He stops 190 feet from the base of the building at the tip of the building's shadow. Round answers to three decimal places.

A. If there was a piece of rope from the top of the building to Joel, how long would it be?
B. What is the angle of elevation from Joel to the top of the building?
C. Margaret says that she could find the angle of depression from the top of the building to Joel by subtracting the angle of elevation from 90. Is she correct? Explain.

Answered by Penny Nom.
Extraneous solutions 2015-03-07
From Emily:
I have a question about Extraneous Solutions, Because I was recently researching to figure out on how to determine that a solution is extraneous and many of the answers talked about how if a answer is negative that it should always be extraneous but now I found out that positive solutions can also be considered as extraneous solutions so that is why I am really confused Extraneous Solution's.
I would really appreciate it if you could clearly explain to me how to determine an extraneous solution from a normal solution.
Thanks,
Emily

Answered by Chris Fisher.
The definition of percent ( % ) 2015-03-07
From Kenneth:
Hello:

I saw this definition online from the Free Dictionary (The Free Dictionary.com) regarding the definition of percent (%):

"Noun 1. a percent sign - a sign (`%') used to indicate that the number preceding it should be understood as a proportion multiplied by 100."

What is this "proportion" multiplied by 100?

When I think of a proportion, I think of a/b = c/d. How can a number preceding the percent sign be understood as a proportion X 100? I thank you for your reply!

Answered by Chris Fisher and Claude Tardif.
A lot on a cul-de-sac 2015-03-06
From ana:
Julie lives on a cul-de-sac and wants to know if the city calculated the area of her plot of land correctly (see diagram below). We can assume the cul-de-sac is a circle and it has radius 40 feet.The boundary of the lot along the cul-de-sac (the arc from A to B) is 78.21 feet. The city found the area to be 7012.5 square feetare they correct?
Answered by Penny Nom.
A man is standing on top of a building 2015-03-06
From kiki:
a man of height 1.5m standing on top of a building of height 48.5m views another building across the square. he observe that the angle of depression of the bottom of the building is 40 degrees and the angle of depression of the top of the building is 5 degrees. Both buildings stand on the same level
a) calculate the distance of the man from the base of the building across the square measured along the line of sight

Answered by Penny Nom.
Two parallel tangents to a circle 2015-03-05
From Samantha:
The equation of a circle is x^2+y^2=25. Determine the equation of the parallel tangent lines to this circle, for which the slope is 4/3.
Answered by Penny Nom.
Integers in different bases 2015-03-05
From Michael:
Let k be a positive integer so that 28 (subscript)k = 132 (subscript)5
Answered by Penny Nom.
The length of a ramp 2015-03-05
From Jaylynn:
Hi, I've been trying to figure out how long my ramp would have to be in order to reach a height of 3.5 feet at a 30 degree angle for a sugar glider enclosure?
Answered by Penny Nom.
Bricks around a fire pit 2015-03-05
From Jayson:
I have a round fire pit. It measures 25 inches in diameter. I have 12 inch long square bricks to go around it . My question is what degree do I cut the ends of these bricks to make them fit around this circle? The brick dimensions are 12"Lx6"Wx4"D.
Answered by Harley Weston.
Istanbul to Lagos 2015-03-03
From Victor:
A plane flies from Istanbul to Lagos at 800km/h and then returns to Istanbul at 900km/h. The return trip takes 1 hour less than the flight to Lagos. What is the distance between Istanbul and Lagos?
Answered by Penny Nom.
Two consecutive positive integers 2015-03-01
From meha:
Find two consecutive positive integers , sum of whose squares is 365.
Answered by Penny Nom.
Solve x=r(t-sin(t)) for t 2015-02-28
From David:
I don't know how to write the function of t(x) by x=r(t-sin(t)).
Can you teach me that?

Answered by Harley Weston.
The radius of a cylinder 2015-02-26
From Rose:
Hi. I want to know how to find the radius of cylinder.
When I have height (35cm) and area of the curved surface(880sq.cm).
I know the formula is 2πr(h+r). But I can't understand how to find it's radius.
Please help me. I really need your help.

Answered by Penny Nom.
Two equations with fractions 2015-02-26
From Pulane:
Hi math centre I've been trying to solve these equations for days now please help (6/x)-(1/y)=4
(9/x)+1=(-2/y)

Please help me solve them simultaneously
Thank you

Answered by Penny Nom.
A question in set theory 2015-02-25
From Jared:
If a set A={1,2,3} and set B={ {}, 1}

Can B be a subset of A? Since every Set contains an {} ?

Answered by Robert Dawson and Claude Tardif.
Two concentric circles 2015-02-25
From Manasi:
The area between 2 concentric circles is 6 times the smaller circle. Radius of small circle is 7 cm. Find the difference in the circumference of the bigger circle ad the smaller circle?
Answered by Penny Nom.
3 over "x" plus 5 2015-02-23
From Kenny:
3 over "x" plus 5. I don't know this is either a polynomial and if so how would you define it.
Answered by Harley Weston.
f(x)=(x^2-1)/(x-1) 2015-02-21
From Ahmed:
Is f(x)=[(x^2-1)/(x-1) and x=2 at x=1] differentiable at x=1 ? Why ?
Answered by Penny Nom.
A region described by inequalities in cylindrical coordinates 2015-02-21
From Rahul:
I am not able to visualize a solid given by inequalities as under (in cylindrical coordinate system) 0= I know that (can visualize) first 2 inequalities say it is a cylinder of infinite length. It seems that third inequality poses the restriction to the height as well as it makes us to remove a cone.
But I just can not understand it clearly.
Thanks in advance!
Regards,
Rahul

Answered by Penny Nom.
Column vectors 2015-02-21
From jill:
A has co- ordinates (7,-1) and B has co-ordinates (3,5).write these as column vectors
Answered by Penny Nom.
A limit 2015-02-19
From genc:
Lim (27x^3-1) / (3x-1)
X-> 1/3

Answered by Harley Weston.
The height of a building 2015-02-18
From prateek:
the height of a flagpole on top of a building is 6m. the angle of elevation of the top and bottom of the flagpole are 45 and 30 respectively. find the height of the building
Answered by Penny Nom.
An isosceles triangle and an arc 2015-02-18
From Sreeharsha:
The diagram shows an isosceles triangle ABC in which BC = AC = 20 cm, and angle BAC = 0.7 radians. DC is an arc of a circle, centre A. Find, correct to 1 decimal place,
(i) the area of the shaded region, [4]
(ii) the perimeter of the shaded region. [4]

Answered by Penny Nom.
5000 gallons in cubic yards 2015-02-17
From Miguel:
If I have a cube shaped tank in the ground that holds 5000 gallons and I want to take it out and fill the hole in with dirt, how much dirt will I need in yards?
Answered by Penny Nom.
Tiling a room 2015-02-16
From Owen:
nicolas room is 56m2 she wants to put tiles down which are 50cm by 50cm each cost 4 how much money will she spend
Answered by Penny Nom.
Two equations 2015-02-16
From nigel:
2x+1/2y=1
6x-3/2y=21

Answered by Penny Nom.
A 330 foot long fence 2015-02-15
From Marsha:
I am putting up a fence 330 feet long and want to put the t post every 4 feet how many t post do i need?
Answered by Penny Nom.
Distance, time and rate for three people 2015-02-15
From Mubashir:
Steven left Town A and walked towards Town B at a speed of 100m/min. At the same time, Jason and Melvin started from Town B and walked towards Town A at a speed of 80m/min and 75m/min respectively. If Steven met Melvin six minutes after passing Jason, find the distance between Town A and Town B.
Answered by Penny Nom.
Bearings and a rectangular plot 2015-02-14
From Mubashir:
A,B,C,D are the four corners of a rectangular plot marked on level ground. Given that the bearing of B from A is 040 degrees and that the bearing of C from A is 090 degrees. Calculate the bearing of
(a)B from C
(b)A from C
(c) D from C

Answered by Penny Nom.
A stone is dropped in a lake 2015-02-14
From Wendy:

Hi, I have problems solving this problem. We didn't exactly go over these kind of problems and the book doesn't have an example either. Thank you for your help!

A stone is dropped in a lake, creating a circular ripple that travels outward at a speed of 80 cm/s.
(a) Find a function g that models the radius as a function of time t.

g(t) =

(b) Find a function f that models the area of the circle as a function of the radius r.

f(r) =

(c) Find f compose g.
f compose g =


Answered by Penny Nom.
Stopping distance 2015-02-11
From Audrey:
A Harley Davidson motor cycle weighing 650 lbs with a rider weighing 175 bs was going 40 miles per hour. He had to make a sudden stop . Slammed on brakes. How long a distance for him to stop?
Answered by Penny Nom.
A word problem with fractions 2015-02-11
From Omokayode:
A vehicle tank was 3/5 full of petrol. When 21 litres of fuel was added it was 5/6 full. How many litres of petrol can the tank hold?
Answered by Penny Nom.
A fence post problem 2015-02-08
From Nicole:
In Susan's rectangular garden plot, she put 12 posts on the long sides and 8 posts on the short sides. How many posts did she use altogether? (The answer is not 40.)
Answered by Penny Nom.
A circle and a chord 2015-02-07
From Dakota:
If the diameter of a circle is 48 cm, find the shortest distance from a chord of length 34 cm to the center of the circle
Answered by Penny Nom.
Speed, distance and time 2015-02-06
From Terry:
How many seconds would it take to travel 0.18 km at a speed of 130km per hour?
Answered by Penny Nom.
The product of a 2-digit number and a 3-digit number 2015-02-06
From Nathaniel:
The product of a 2-digit number and a 3-digit number is about 50 000 what are the products
Answered by Penny Nom.
2x^2-2x+1=4x+1 2015-02-06
From Caitlyn:
2x^2-2x+1=4x+1
Answered by Penny Nom.
The center and radius of a circle 2015-02-06
From ariana:
I need to find the center and the radius of this circle. I don't know how to put 9/2 than square it into a fraction.

x^2 + 2x + y^2 +9y=5

Answered by Penny Nom.
The volume of a cone 2015-02-05
From Linda:
How do you calculate the volume of a cone that is 25cm high and has an angle of 20 degrees?
Answered by Penny Nom.
A parallelogram inscribed in a circle 2015-02-04
From narendra:
how can we prove that a circular parallelogram is a rectangle?
Answered by Chris Fisher.
Two cars pass each other going in opposite directions 2015-02-03
From Caroline:
Two cars pass each other going i opposite directions. One car is going 100 km/h and the other is going 80 km/h. How far apart will the two cars be after driving 45 minutes at these rates of speed?
Answered by Penny Nom.
A train from Vancouver to Whistler 2015-02-02
From Tea:
Serena and Nina are taking a train from Vancouver to Whistler, a 160km trip. If the average speed is decreased by 16km/hr, the trip will be 1/2 hours longer. What is the average speed of the train? Thanks :)
Answered by Penny Nom.
Jack and Jill climb two poles 2015-02-02
From APRIL:
Two vertical poles are 3 meters apart. Jack is climbing one pole while Jill climbs the other. If the distance between Jack and Jill is 5 meters, how much higher is Jill than John?
Answered by Penny Nom.
Comparing fractions 2015-02-02
From shealla:
Please help me with my assignment please I'm having trouble answering this one..
Write the larger fraction in each pair..
A. 2/3, 4/7 B. 1/3, 2/5 C. 5/8, 3/5

Answered by Penny Nom.
Ratio of gas to oil 2015-02-02
From Chris:
I would like to find the gas oil ratio for a 2 cycle engine. I have the gallons of gas and the ounces of oil used by the engine, but I want to find what the ratio is. For example I used 5.675 gallons of gas and 5 ounces oil what is the ratio? Please explain step by step, and I understand there are 128oz in a gallon.
Answered by Harley Weston.
Shadow angle 2015-01-29
From Lorilyn:
A pole,110meters high,cast a shadow of 35meters long,what is the angle
Answered by Penny Nom.
The volume of Lake Utah 2015-01-29
From Hannan:
Lake Utah has a surface area of 3,846 square miles and an average depth of 10.5 feet. In cubic miles, how much water does it hold? How would you approach this question? Where would you start?
Answered by Robert Dawson and Penny Nom.
128/(-16)/(-2) 2015-01-28
From jackie:
128/(-16)/(-2) I was wondering if you can show me how to work this question out
Answered by Harley Weston.
What is our cost? 2015-01-27
From Johanna:
I have a pieces of 3/4" sch40 (round tube) 240" long at $70. What is our cost. We also add 35% to our cost for selling price. How do I figure this out?
Answered by Penny Nom.
The height of an obelisk 2015-01-27
From Fabian:
Two observers on level ground position themselves 50 meters apart so that an obelisk is due north of position A and due west of position B. The angle of elevation to the top of the obelisk at position A and B is measured to be 29.9 degrees and 37.5 degrees respectively. Use this information to estimate the height of the obelisk.
Answered by Penny Nom.
Is a square a trapezoid? 2015-01-26
From Katie:
Can a trapezoid sometimes be a square?
Answered by Penny Nom.
Russell is 6 years older than Samantha 2015-01-26
From Kelli:
Russell is 6 years older than Samantha. In 4 years the sum of their ages will be 78. How old is Russell now?
Answered by Penny Nom.
A road around a garden 2015-01-25
From hahha:
a garden 150 m long and 80 m wide has a road 4 m wide all around on the out side find the cost of paving at the rate of 12 per s.q m
Answered by Penny Nom.
A motorbike race 2015-01-25
From Pramegh:
In a motorbike race of 75 km, the winner completes the race with a lead of 300 meters and 8 seconds before the second rider. Considering the riders ride with an average speed, find the difference between their speeds with which they completed the race.
(Calculate up to 2 decimal places)

Answered by Penny Nom.
Two concentric circles 2015-01-25
From nazneen:
select the correct answer from the given four options

given are two concentric circles. radii of outer circle & inner circle are r1 & r2 respectively. the areas of inner circle & shaded ring are equal. the radii r1 & r2 are related by?

1. r1 = r2
2. r1 = r2*square root 2
3. r1 = r2*square root 3
4. r1 = 2r2

Answered by Penny Nom.
sin x = cos x 2015-01-23
From Mubashir:
there are two curves y=sinx and y=cosx intersecting at point where x is less than 90 and greater than 0.to find the point I made a equation sinx=cosx but donot know what to do further .please help me by solving this equation sinx=cosx also tell me that have you solved this equation by reference to the graph or by other means please do elaborate your solution in your answer.
Answered by Penny Nom.
A schedule for observing our peers 2015-01-23
From Jennifer:
I am a sales trainer. Each month we need to observe one of our peers and give feedback. What this means is every month, not only am I observing someone, but someone is also observing me. For example, in January, Amy observes Tracy, Tracy observes Rachel, Rachel observes Ryan, and so on. The last person would then observe Amy, bringing it full circle. There are 10 trainers on my team. How do I set it up to where each trainer observes another trainer only once over the course of the year (and in return, each trainer is only being observed once by each person)? I know they will eventually repeat but would that start in the 10th month?
Answered by Robert Dawson.
A schedule for 5 employees working 2 at a time 2015-01-23
From Cynthia:
We have 5 employees and need only 2 to work on Saturdays. what is the best way to fairly schedule everyone. PS. from time to time a sixth person will be thrown in to make things really interesting.
Answered by Victoria West.
Mary gave her sister 5/8 of her nuts 2015-01-22
From Valence:
Mary gave her sister 5/8 of her nuts. Her sister gave her friend 2/3 of the amount, and her cousin 1/3 of the remainder. If Mary's sister had 50 nuts left, how many nuts had Mary.
Answered by Penny Nom.
Scheduling meetings with pairs of people 2015-01-22
From Jacey:
I am trying to figure out a formula/system to pair up a list of people so they meet with each other every month, but they rotate who they meet with. Right now I have 13 people and I would like to just type in their names and then have the system put each person with someone else every month and rotate so no one gets the same person twice. Can this be done?
Answered by Victoria West.
The game of 24 2015-01-21
From aaron:
24 game whants me to use 11 14 5 and 9 to make 24 allowed (+ - dividing and multiplying)
Answered by Penny Nom.
Math in the universe 2015-01-21
From GA:
I want to find out examples in universe for this equation:
sin(x)/cos(x)=1 or tan(x)=1. I know the mathematical answer of pie/4 or 45 degree angle.

What I need to know is to find examples of this. I found an example in construction, for example, which is the shape of attic in the house.

I want to find examples in universe like in solar system, in quasars or jets coming out of them, in galaxies, in stars, in black holes, etc

Do you know of any such examples?

Answered by Robert Dawson.
The volume of a swimming pool 2015-01-21
From kirara:
Find the volume of water in a swimming pool with vertical ends and sides. The length measured at the water line is 50 ft. And the breadth is 20 ft. The bottom of the swimming pool is a plane sloping gradually downward so that the depth of the water at one end is 4 ft. And at the other end is 8 ft.
Answered by Penny Nom.
1,4,9,61,52,___ 2015-01-21
From Mubashir:
1,4,9,61,,52,___,84,___,18,1,121,___ please tell me its formula and also that rule that is being applied here like adding 3 or subtracting 5 etc.
Answered by Walter Whiteley.
The height of a building 2015-01-20
From Emily:
A man 2m high observes the angle of elevation to the top of the building to be 70 degrees. And the angle of depression to the bottom of the building to be 19 degrees. How tall is the building?
Answered by Robert Dawson.
Two cars 2015-01-18
From taylor:
two cars leave the park at the same time, one traveling north at a speed 10 mph faster than the other which is traveling south. after 3 hours the cars are 420 miles apart. find the speed of both cars
Answered by Penny Nom.
Pumping water from a borehole 2015-01-18
From patience:
An empty tank for storing water from a borehole has a volume of 480 cubic metres. If it is filled by a pump that pumps water at a rate of 16 litres per second, how many hours will it take the pump to fill this tank please show all calculations
Answered by Penny Nom.
1 + cot x divided by sin x + cos x 2015-01-15
From Torrie:
I need to solve this problem in terms of Sin, but I'm having trouble. 1 + cot x divided by sin x + cos x
Answered by Robert Dawson and Penny Nom.
Largest cone in a sphere 2015-01-15
From Alfredo:
What is the altitude of the largest circular cone that may be cut out from a sphere of radius 6 cm?
Answered by Penny Nom.
Percentage change 2015-01-14
From Jim:
When using a scale e.g. 0-10, what is the formula for calculating percentage change. For example when someone answers a questionnaire where a question has a 0-10 scale, and they score a 4 first time, and then they answer the same questionnaire a different day, and they score an 8, how do I calculate the percentage change.
Answered by Penny Nom.
A sequence 2015-01-13
From cyaz:
write a rule for each sequence then find next 3 terms for 7/8, 3 1/8, 5 3/8
Answered by Penny Nom.
An input/output table 2015-01-13
From Rose:
How do you create an input/output table when the rule is: the output is a +5?
Answered by Harley Weston.
$xx,xxx million 2015-01-12
From sherry:

as a financial editor, for years I've seen $\$$ amts like this:
$\$xx,xxx$ million (ie, with a comma, not dec point)
Isn't that thousands of millions, which would equal 'billions'?


Answered by Penny Nom.
An investment for 20 months 2015-01-12
From rose:
Darnell wants to have 2700$ to purchase a tv in 20 months. what will he need to deposit today if he earns 5% annual interest compounded monthly
Answered by Penny Nom.
h+h+h = -9 2015-01-12
From juanita:
How to solve h+h+h = -9
Answered by Penny Nom.
The length of a roll of paper 2015-01-12
From Peggy:
roll of paper 3ft wide and roll equals 500 sq ft how long would the roll be?
Answered by Penny Nom.
A difference quotient 2015-01-12
From Sasha:
Simplify the difference quotient

f(x) − f(a)/ x-a
if x ≠ a.
f(x) = x^3 − 12


Answered by Penny Nom.
The volume of a lake 2015-01-10
From Peter:
If a lake is 8 acres in size and 10 feet deep how many gallons of water does it contain
Answered by Penny Nom.
Mutually prime composite numbers 2015-01-09
From nivedita:
Two composite number that is mutually prime?
Answered by Penny Nom.
Selling items at a reduced price 2015-01-09
From Kent:
I have an item I sell for $19.95 and make a profit of $10.97 for each sale. If I reduce the price to $14.97, my profit is $5.99 each sale. Is there a formula to determine how many more I would need to sell at $5.99 per sale to make the same net cash (profit) as selling at $10.97 per sale?
Answered by Penny Nom.
The units digit of a prime 2015-01-08
From Patricia:
Every prime number greater than 10 has a digit in the ones place that is included in which set of numbers below 1 3 7 9 or 1 3 7 or 0 2 4 5 6 8 or 1 3 5 9
Answered by Walter Whiteley.
Missing digits in a phone number 2015-01-07
From Janelle:
I had a friend try and play a game on me, regarding phone numbers, so I only know the area code , and the last four digits of the phone number. Which means, there are 3 digits that I need to figure out all the possibilities to.
Answered by Penny Nom.
Scheduling 12 for lunch 2015-01-05
From Sabrina:
I have 12 staff members that need to have lunch together 1 time each week. I am trying to pair them in a way that we each have the same amount of lunches in the same amount of weeks. Please Help! Thanks!
Answered by Victoria West.
The degree of a polynomial 2015-01-05
From Nichole:
How do I determine the degree of polynomials? I've searched this on sites but they are all so confusing! Is there a simple explanation or way to find what the degree is? Some examples are: 6x^4 10x^2yz^5 and 3m^2n^7-10m^8. I also have to say that I am under the impression that this symbol ^ means the number after it is an exponent.
Answered by Robert Dawson and Harley Weston.
A silo is composed of a hemisphere and a cylinder 2015-01-03
From Ami:
A silo is composed of a hemisphere and a cylinder. The total height for the silo is 20m and the diameter of the silo is 8m. What is the volume of the silo to the nearest cubic meter?
Answered by Penny Nom.
Filling a tub 2015-01-02
From Mr:
The cold tap can fill a bath in 5minutes,the hot tap in 15,and the waste pipe empty the full bath in 10 minutes. All three are fully open for 2 minutes,after which the waste-pipe is closed. How much longer will it take to fill the bath?
Answered by Penny Nom.
1 + 2 + 3 + ... + (2n - 1) 2015-01-01
From Brian:
Hi Maths Central
My wife presented me with a query which may have a simple answer, but one that I cant deduce or explain.

Take the string of numbers, n=1,2,3,4,5
It seems that n(2n-1) = Sum((1..(2n-1))
e.g. for n=5, both 5 x 9 and Sum(1.9) equal 45, and so on for other values of n.

Could you please provide an explanation? Does it have an underlying reason and a name?

Look forward to your response.
Brian

Answered by Penny Nom.
An isosceles triangle 2014-12-31
From ahmadmahmoud:
an isoseles triangle is such that each of the base angles is twice the vertical angle.Find the angles of the triangle
Answered by Penny Nom.
1.5% of 1 trillion 2014-12-30
From Kgosi:
How much is 1.5% of 1 trillion?
Answered by Penny Nom.
Rates, percentages and units 2014-12-30
From Kenneth:
Hello:

If percentages have no units, why are some percentages called rates, as in interest rate, or perhaps a tax rate of 7% as an example? A rate has units of different quantities.

I thank you for your reply.

Answered by Robert Dawson.
Curvature of the Earth 2014-12-29
From Jimmy:
Both batteries died in my scientific calculator and I have lost my formula for the heigth of the curvature of the earth between two points on the surface. I used degrees and miles. I only had to enter the distance between the two points on the surface and the formula gave me the hieght the earth raised between the two points.
Answered by Robert Dawson.
196 kilometer in2 hours 2014-12-29
From Ekanem:
QQ A motorist had planned to reach a place 196km in two hrs exactly. For the first 15km he was able to average only 40km/h. What average speed must he keep up for the rest of the journey if he is to arrive on time.
Answered by Penny Nom.
The perimeter of a quarter circle 2014-12-26
From Maisy:
This is the question that I got for a math worksheet.
The radius of a quarter circle is 5 miles. What is the quarter circle's perimeter?
Use 3.14 for pi.

Answered by Penny Nom.
A trip to Ottawa from Toronto 2014-12-22
From Kristy:
A trip to Ottawa from Toronto will take 4 1/2 hours. Assuming we are 2/3 the way there, how much longer will the trip take?
Answered by Penny Nom.
A tangent to a circle 2014-12-22
From azman:
Find the equation of the tangent line to the circle x^2+y^2=9 at the point P (2, square root of 5).
Answered by Penny Nom.
Discount 2014-12-20
From nirmala:
A bag is marked at rs 800 and is sold for rs 68. Find the rate of discount
Answered by Penny Nom.
211basex=152base8 2014-12-15
From Humaira:
211basex=152base8
Answered by Penny Nom.
A line segment of length root 5 2014-12-15
From angela:
On the dot grid below, draw and label a line segment with length square root 5 the dot grid is 8 by 10
Answered by Penny Nom.
A cone is 2/3 full of sand 2014-12-14
From Janice:
A cone with a radius of 3.5 cm and a height of 12 cm is 2/3 full of sand.
What is the volume of the sand inside?

Answered by Penny Nom.
A right triangle 2014-12-13
From Katie:
the shorter leg of a right triangle measures 2 feet less than the longer leg. the hypotenuse measure 10 feet. find all three sides
Answered by Penny Nom.
Planar curves 2014-12-13
From ann:
what does planar curve mean in your definition of a cone?
Answered by Penny Nom.
A cuboid 2014-12-11
From Nehal:
Six cubes have a surface area of 24 cm2. They are joined together to male a cuboid. What could the surface area of this cuboid be? There are two different answers.
Answered by Penny Nom.
Remainder 2014-12-08
From Muqadasah:
A number, when divided by136, leaves remainder 36. If the same number is divided by 17, what will be the remainder?
Answered by Penny Nom.
30% profit 2014-12-05
From Lyn:
I would like to know a formula that I would use on a standard calculator to calculate a 30% profit margin on an item. If I purchased an item at $7.70 how would I calculate 30% profit for me, not just 30% mark up?
Answered by Penny Nom.
A circle through 3 points 2014-12-04
From priyanka:
Find the equation of a circle passing through the origin and intercept on axes are a and b.
Answered by Penny Nom.
Shaking hands at a party 2014-12-03
From Nazrul:
At a party, everyone shook hands with everybody else. There were 66 handshakes. How many people were at the party?
Please help me.

Answered by Penny Nom.
How do you change a decimal to a ratio? 2014-11-29
From Esmeralda:
How do you change a decimal to a ratio? Express the decimal 0.2 as a ratio.
Answered by Penny Nom.
1999 equations in 1999 unknowns 2014-11-28
From Subrahmanya:
Solve the following system of 1999 equations in 1999 unknowns :

x1+x2+x3=0, x2+x3+x4=0., x1997+x1998+x1999=0,

x1998+x1999+x1=0, x1999+x1+x2=0.

(in x1,x2,...................,x1999 the numbers 1,2,.............,1999 are subscripts)

Answered by Penny Nom.
Even and odd 2014-11-28
From Subrahmanya:
n1, n2, n3....................,n1997 are integers not necessarily distinct. (actually in n1, n2,.............., n1997 the numbers 1,2,.................,1997 are subscripts of 'n')

X= (-1)^n1+(-1)^n2+............+(-1)^n998

Y=(-1)^n999+(-1)^n1000+............+(-1)^n1997

Then

which of the following options is true

A) (-1)^X = 1, (-1)^Y = 1 B) (-1)^X = 1, (-1)^Y = -1
C) (-1)^X = -1, (-1)^Y = 1 D) (-1)^X = -1, (-1)^Y = -1
E) none of these

Answered by Penny Nom.
Exponential notation 2014-11-27
From Jaqui:
May sound super easy, but how would you SHOW that you simplified 3x3 to the power of 2 (the little 2)?

thank you!

Jaqui

Answered by Penny Nom.
What is 20 and 3/5 of 10? 2014-11-26
From Jeannine:
What is 20 and 3/5 of 10? Question is written exactly this way. Is this 20 3/5 times 10 (103/5 times 10), or is it 20 and (3/5 times 10)?
Answered by Penny Nom.
Mark's book case 2014-11-24
From anne:
mark has 312 books in his case. he has 11 times as many fiction books as non fiction books. how many fiction books does mark have?
Answered by Penny Nom.
Cutting a hexagon with a sliding miter saw 2014-11-23
From Joseph:
I need the angles in degrees for a hexagon one side is 18inches on the outside the problem I am having is in the angle of the cut and I am using a sliding miter saw which only goes from0 degrees to 45 degrees so I need help in getting the angle of the cut
Answered by Harley Weston.
A truncated, square-based pyramid 2014-11-23
From Hannah:
A designer vase has the shape of a truncated, square-based pyramid. The base of the vase is a square with a side length of 15 cm. The area of the square opening is 70.56 cm2. Each of the four sides is a trapezium with slant sides 9 cm long. Find (to the nearest square centimetre) the total surface area of the vase.
Answered by Penny Nom.
Doubling the dimensions of a cone 2014-11-21
From Hannah:
If the volume of a cone of height 10 cm is 261.8 cm3, show that this volume is increased by a factor of 8 if the dimensions of the cone are doubled.
Answered by Penny Nom.
Two quadratic equations 2014-11-20
From rajesh:
Sir,
I would like to discuss on question-
-Find the value of variable X and Y, equations are
X2+Y2+2XY=25
X2+Y2-2XY=1

Sir, my point is equation looks not so easy.My opinion is there many (more than 4)value possible for both X and Y.
Kindly help me.
Waiting for your response.
regards,
rajesh

Answered by Penny Nom.
Factorise 15x + 15y 2014-11-20
From Jordan:
hi i saw a question in class today that i didn't understand and i didn't really understand what my teacher was going on about so how do you factorise 15x + 15y
Answered by Robert Dawson and Penny Nom.
An arithmetic progression 2014-11-19
From Gbenga:
In an A.P the difference between 8th and 4th term is 20. The 8th term is 1\2 times the 4th term . Find arithmetic progression..
Answered by Penny Nom.
Two ships 2014-11-18
From Laura:
7. A ship leaves its home port and sails on a bearing of N28.17E. Another ship leaves the same port at the same time and sails on a bearing of S61.83E. If the first ship sails at 24 mph and the second at 28 mph find the distance between the two ships after 4 hours.
Answered by Robert Dawson.
An age related word problem 2014-11-18
From Cole:
Susan and Russell are brother and sister. Susan says that in two years she will be twice Russell's current age. Russell says that he's only three years younger than Susan. How old is each of the siblings?
Answered by Penny Nom.
How many square feet in 10 gallons of liquid at 1/4 in thick? 2014-11-14
From Rich:
How many square feet in 10 gallons of liquid at 1/4 in thick
Answered by Penny Nom.
(x-3)^2-(x+3)^2 2014-11-13
From Bernice:
(x-3)^2-(x+3)^2
Answered by Penny Nom.
1/6k=-11 2014-11-13
From Marty:
Using the balance method, what is the answer to 1/6k=-11, trying to find what k equals. Thanks
Answered by Penny Nom.
An irregular convex octagon 2014-11-13
From james:
I have an irregular convex octagon, alternating between 4 large edges, say 'a' mm long and 4 small edges, say 'b' mm long, is there a formula available so that I can work out the minimum size sit a circle with a radius of 34.25mm inside it thank you
Answered by Chris Fisher.
The cube root of 729 2014-11-12
From Alexis:
What would be the square root of 729 to the third power and could you explain how to get the answer?
Answered by Penny Nom.
What is -3 squared? 2014-11-12
From Christine:
On a math test, it said "What is -3 squared?" It did NOT say "What's is (-3)squared"

The teacher's explanation is that if there are no brackets or parenthesis, you ALWAYS square the number first then do the negative, so the answer should be -9, but I can't find anywhere that confirms this.

Help please.

Answered by Robert Dawson.
Some geometry problems 2014-11-07
From Maria:
Hi there,
My name is Maria and I'm a student in Ireland.
Can you pleeeease help me with questions 1 to 4 on the attached file. I'm really stuck:

Answered by Penny Nom.
The area of a pentagon 2014-11-04
From Gracie:
i really need help with this problem in my math book, will you help?

"Derrick drew regular pentagon with side lengths of 8 centimeters. He divided the pentagon into 5 identical triangles, and measured the height of one of the triangles to be 5.5 centimeters. Find the area of the pentagon."

this really makes no sense to me. Can you help me with anything to make it easier?

THANKS!!!!!

Answered by Penny Nom.
The area of a circle in terms of the circumference 2014-11-04
From Sarah:
How do you find the area of a circle if you already have the circumference? There was one answer to this question already but it didn't make sense to me, because they rounded up pi which you can't do so the answer is incorrect. thanks
Answered by Penny Nom.
A quadratic function modelling the heightof a flea jump 2014-11-02
From Hannah:
A flea jumps from the ground to a height of 30 cm and travels 15 cm horizontally from where it started. Suppose the origin is located at the point from which the flea jumped. Determine a quadratic function in vertex form to model the height of the flea compared to the horizontal distance travelled
Answered by Penny Nom.
The density of sea sand 2014-11-02
From Lenny:
Hi There,

I need to find out the the density of sea sand to convert one metric ton to cubic meter as I am submitting for a tender which is in cubic meter but the requirement is in metric ton. I searched through the web site but no density of sea sand is given though there is specific Gravity of dry sand is available. I was given a density of 1.6 to work with. If that is true am I right to say that 1 cubic meter of sea sand is equivalent to 1.6 metric ton? Please help as I am getting confused with what I am able to find out on the web.
Thanks much in advance
Rgds
Lenny

Answered by Penny Nom.
4 card hands 2014-11-02
From Ronaldo:
How many Mus hands (combination of 4 cards allowing repetitions) can be made from a deck containing 8 types of cards?

RRRR, RRRC, RRRS, RRR7, RRR6, RRR5, RRR4, RRRA,
RRCC, RRCS, RRC7, RRC^, RRC5, RRC4, RRCA,
RRSS, RRS7, etc.

I think 330. If so, what is the formula?

Answered by Penny Nom.
Jason's speed 2014-10-31
From jason:
the speed of Jason is 12 times faster than everyone. The speed of Jason is 108mph. Write the equation and solve to find the speed of everyone else.
Answered by Penny Nom.
Prime factorization in exponent form 2014-10-31
From Emma:
I need to find out how to make a prime factorization of 120 in exponential form.
Answered by Penny Nom.
What is the speed of the boat in still water? 2014-10-30
From Adam:
The current in a stream moves at a speed of 2 km/h. A boat travels 38 km upstream and 38 km downstream in a total time of 3 hr. What is the speed of the boat in still water?
Answered by Penny Nom.
Two quadratic polynomials 2014-10-28
From khushboo:
The zeroes of a quadratic polynomial x^2+ax+b are 'c' and 'd' and the zeroes of a quadratic polynomial x^2+cx+d=0 are 'a' and 'b'. find the numerical value of a+b+c+d where a, b, c and d are non zero integers.
Answered by Penny Nom.
The region between two concentric circles 2014-10-27
From Ray:
two circles, concentric; Given the length of chord of outer circle that is tangent to inner circle. what are the areas of both? how to calculate?
Answered by Penny Nom.
logbase4 (sin x) = -0.5 2014-10-26
From Susan:
Solve for x: logbase4 (sin x) = -0.5
Answered by Penny Nom.
6 bolt holes around a circle 2014-10-26
From Bobby:
What Is The Cord Dimension For 6 Holes On A 24" Bolt Circule
Answered by Penny Nom.
Find the nth term 2014-10-26
From Kenneth:
According to the pattern of the following sequence. Find it's nth term: 3,9,27,81,243,..........
Answered by Penny Nom.
Revolutions per minute 2014-10-24
From Edward:
Hello; I have a 28.2 inch diameter tire; do not worry about engine RPM or gear ratios, please tell me what the RPM of that tire is at 8 MPH and 64 MPH. Thank you.

Sincerely; Edward

Answered by Penny Nom.
A truncated square-based pyramid 2014-10-22
From Beth:
How do you find the height of the original square-based pyramid when given the sides (12cm) of the base and height (6cm) of the truncated pyramid, as well as the sides (3cm) of the base of the chopped off top (chopped off parallel to the base)?
Answered by Penny Nom.
A 10-foot piece of PVC pipe 2014-10-21
From David:
A plumber has a 10-foot piece of PVC pipe. How many 9/5-foot pieces can be cut from the 10-foot piece ?
Answered by Penny Nom.
Three consecutive odd integers 2014-10-17
From Maddy:
3 times the largest of three consecutive odd integers is 13 more than the sum of the other two. What are the integers?
Answered by Penny Nom.
Water in a spherical container 2014-10-17
From Natalie:
A spherical container with radius 10cm being filled with water such that the water level, h cm, in the container increase at a rate of 0.5 cm s^(-1). Show that the area of the horizontal surface of water, A cm^(2), in the container is given by A = π(20h - h^(2) ).
Answered by Penny Nom.
A poorly worded question 2014-10-14
From Marjorie:
How do I figure out the following? Dylan's dog weights 12 times more than his pet rabbit. The dog and the rabbit weight 104 pounds. How much does Dylan's dog weigh? Would you explain in detail how I would arrive at the answer so I can convey same to my grandson who is in the 5th grade. Thanks.
Answered by Penny Nom.
A linear system 2014-10-14
From pheter:
4/x - 1/y = 3 .... equation (1)
6/x - 2/y = 5 .... equation (2)

Answered by Penny Nom.
A fact family containing 4, 4 and 16 2014-10-14
From Leslie:
I am helping my son and the question is 4,4,16 in fact family what does that mean
Answered by Penny Nom.
How does pir^2 = 1/4pid^2? 2014-10-14
From al:
Hi I cant work out the algebra. How does pir^2 = 1/4pid^2 Thanx
Answered by Penny Nom.
Building an 8 sided box 2014-10-14
From Michael:
I want to build an 8 sided box. The North, East, South, and West sides I want them to be 4 feet in length.
The NE, SE, SW, and NW sides I want to be 2 feet in length. What angles do I need to cut my angles.
Thanks Michael

Answered by Penny Nom.
15 - (5-x)/ x = 30 2014-10-13
From AMANDA:
15 - (5-x)/ x = 30

I thought you had to multiply both sides by x in order to remove the fraction?

15x - 5x - x2 = 30x

then combine 10x - x2 = 30x

-x2 =20x

then take the sqrt of each side...

what am I doing wrong??

Answered by Penny Nom.
Pre algebra 2014-10-12
From mohamed:
i want to know the meaning of pre algebra
Answered by Penny Nom.
A quarter mile row of trees 2014-10-09
From junna:
a farmer would like to plant trees on one side of his lot which is 1/4 of a mile in a length His friend advised him that if he would plant the trees 5 feet farther apart,he would need 44 fewer trees.If the farmer would take the advice, how many trees would he plant?
Answered by Penny Nom.
Why express fractions in lowest terms? 2014-10-09
From John:
I teach in a Faculty of Education. A colleague in the university asked me about fractions and lowest terms. I am quoting the person below, and would appreciate your insights into the question/thought.

"One I'm struggling with is why (for example) 6/18 is not considered as good an answer to a fraction question as 1/3. The traditional response is that 6/18 is not in lowest terms so the question has not been finished until the fraction is reduced, but what actually makes the lowest terms answer the better one? Is it convention? Is there a way to explain why simplest form answers in fractions are right and and anything else is considered incorrect without alluding to some need for this 'good habit' elsewhere in math or science? Is there a real-life reason?" Thank you for any insights and if you have nothing to offer to this query, that is fine too. I appreciate your consideration. John

Answered by Robert Dawson.
A 20% markup 2014-10-09
From Fatima:
What is the 20% markup price of $1.50
Answered by Penny Nom.
Maximizing the ticket revenue 2014-10-07
From Allen:
An airplane whose capacity is 100 passengers is to be chartered for a flight to Europe. The fare is to be $150 per person, if 60 people buy tickets. However, the airline agrees to reduce the fare for every passenger by $1 for each additional ticket sold. How many tickets should be sold to maximize the ticket revenue for this flight?
Answered by Chris Fisher.
One zero to a quadratic expression 2014-10-06
From Kevin:
Find a value of n such that f(x) = 3^x2 + nx + 6 only has one zero, is this the only solution to the question?
Answered by Penny Nom.
A tennis ball in a triangular prism 2014-10-06
From Anna:
Hi, I need to find the the base and the height of a triangular prism, but I only know the diameter of a tennis ball that fits exactly in the triangular container.. The diameter for the ball is 8.50cm. Can you help me find the formula? Thank you!
Answered by Penny Nom.
A factoring problem 2014-10-05
From Gina:
3x^2+6x+3
Answered by Penny Nom.
Sieve of Eratosthenes 2014-10-03
From Hope:
using Sieve of Eratosthenes to determine for in instance prime numbers between 1 to 200, to what nth number should i stop?, 4th, which is 11 or what?
Answered by Robert Dawson.
Percentages in a mixture 2014-10-02
From viola:
Hi there

can you help me convert the below so it makes 100% (individual %)

400 gr =
100 gr =
50 gr =
50 gr =
20 gr =
2 gr =
1 gr =
1 gr =

Be great to hear back from you

Thank you

V

Answered by Penny Nom.
Trig functions and the unit circle 2014-10-02
From Jake:
I was wondering what conclusions can be drawn about the trigonometric functions and how they work about the circle. Can you also please give me an explanation for it? Thank you.
Answered by Penny Nom.
Division in base 3 2014-09-30
From Nnubia:
1021 in base 3 divided by 2 in base 3
Answered by Penny Nom.
A lost combination 2014-09-28
From Kim:
I cannot remember my combo to this simple lockbox. It is 3 digits- from 0-9. They can be used more than once . I thought it was 117..but no joy. I am fairly sure it was using those digits 1, and 7. can you give me a list of all possible combinations, using 1s and 7s, for the 3 number code? Thank you and I am in awe of people who have math skills, for I certainly do not.
Answered by Penny Nom.
A rectangle and a triangle 2014-09-27
From rajesh:
The perimeter of a rectangle is equal to the perimeter of a right-angled triangle of height 12 cm if the base of the triangle is equal to the breadth of the rectangle, what is the length of the rectangle?
Answered by Penny Nom.
A man a ship and a wharf 2014-09-26
From Ralph:
A man om wharf 12 meters above the level of water is pulling a rope tide to a boat at the rate of 2 meters per minute. How fast is the boat approaching the wharf when there are 20 meters of the rope our. (with solution)
Answered by Penny Nom.
A wire is bent to form a right triangle 2014-09-25
From Lorena:
A wire 24 dm is bent to form a right triangle. The ratio of the shorter leg to the hypotenuse is 3:5. Find the length of the longer leg?
Answered by Penny Nom.
Two equations in x and y 2014-09-25
From seyilogo:
solve y=2x - 3 and (4x - 2y) / x + y = 1 simultaneously
Answered by Harley Weston.
Continuity on a closed interval 2014-09-21
From Pragya:
The trouble I'm having is as follows :
a continuous function is most of the times defined on a closed interval, but how is it possible to define it on a closed interval ,because to be continuous at endpoints of the interval the function's limit must exist at that endpoint,for which it has to be defined in its neighborhood,but we don't know anything about whether the function is always defined in the neighborhood.
Please help...

Answered by Penny Nom.
A quadratic equation 2014-09-20
From Najah:
(E): (m2_1)x2 _ (m+3)x+4_m2=0
A) for what values of m is the equation (E) quadratic?
B) for what value of m is the real number -1 a root of (E)

Answered by Penny Nom.
The perimeter of a parcel of land 2014-09-18
From Shirley:
What is the perimeter of a parcel of land that is 564 acres square
Answered by Penny Nom.
Meetings for 77 students 2014-09-18
From Adam:
We have a new group of students starting, and would like to set up a series of small group meetings so each student meets each other, hopefully without meeting the same people twice.

We have 77 students. In theory I would like to have 11 meeting slots, with 10 groups in each slot, with up to 8 students in each group. Is there a way to do this?

I have wondered if it might be easier to do 9 meeting slots, with 9 groups per slot, with 9 students per group. Thanks!

Answered by Victoria West.
Two equations in two variables 2014-09-18
From Susan:
(28x + 36y) - [20000 - .75(28x + 36y) + 60000] = 5000
x + y = 10000
solving two equations involving variables

Answered by Penny Nom.
How much did each dog weigh? 2014-09-16
From Fred:
LJ owned two dogs that weighed a total of 140 pounds. If one dog weighed 10 pounds more than the other, how much did each dog weigh
Answered by Penny Nom.
A tangent to a curve passing through a point not on the graph 2014-09-15
From Aquilah:
For the curve y = x2 + 3x, find the equations of all tangent lines for this graph that also go through the point (3, 14).
Answered by Penny Nom.
A six team track schedule 2014-09-15
From Paul:
I need to make a six (6) team track schedule. It needs to be five (5) triangular (3 team) meets with each team playing each team twice
Answered by Victoria West.
Grandpa had an apple tree 2014-09-14
From Emma:
Grandpa had an apple tree. On the first day half of the apples plus one fell to the ground. On the second day, half of the remaining apples plus one fell to the ground. On the third day, half of what was left plus one fell to the ground. The tree was left with only one apple now. How many apples did the tree produce originally?
Answered by Penny Nom.
Two chords in a circle 2014-09-13
From Carlos:
Find the length of the radius of a circle in which a chord of length 6 units is twice as far from the center as a chord of length 12 units
Answered by Penny Nom.
The average of 9 numbers is 45 2014-09-12
From rizza:
The average of 9 numbers is 45. If 90 and 88 are added to the set of numbers. What will be the resulting average?
Answered by Penny Nom.
The average age of a group of 10 students 2014-09-11
From sujan:
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group . What is the average age of the two new students who joined the group?
Answered by Robert Dawson and Penny Nom.
The perimeter and diagonal of a rectangle 2014-09-10
From niniha:
the perimeter of a rectangle is 68cm.if the diagonal is 26, find its dimensions
Answered by Penny Nom.
Base 6 2014-09-10
From Amanda:
using base 6, what is the next number after 25? 35? 55? and 455?

I need to be able to show the base 6 material.

Answered by Penny Nom.
35 base 6 2014-09-10
From Amanda:
Sorry I am having trouble understanding base,

35 in base 6 means 3 10's and 5 ones, which is the same ____ in base 10?

Answered by Penny Nom.
211(base x)=152(base 8) 2014-09-09
From Vaidehi:
Find the base value (i.e. x):
211(base x)=152(base 8)

Answered by Penny Nom.
A second grade word problem 2014-09-09
From Beth:
How do I explain to my second grader how to find the answer to the problem:
My tens digit is 8 more than my ones digit. My ones digit can not be zero.

Answered by Penny Nom.
Problem solving 2014-09-08
From hubert:
a car left the house and travelled at an average speed of 60 kph.how many minutes will it take for the car to reach the school which is 8 km away from the house
Answered by Penny Nom.
A secret number 2014-09-08
From jai:
it is smaller than half of 100, it is more than 4 tens and less than 5 tens, the tens digit is two more than the ones digit , together the digits have a sum of 6..... What is my secret number?
Answered by Penny Nom.
The diagonals of a cube 2014-09-04
From Rukshanth:
How many diagonals does a cube have?
Answered by Harley Weston.
The sum of two numbers is 52 2014-09-01
From Blake:
The sum of two numbers is 52 and the difference is 10. What are the numbers? i used to be real good at this stuff?
Answered by Penny Nom.
Interior angles in a parallelogram 2014-08-30
From xavier:
so, one of my math homework questions requires me to know how to find out how to find the interior angles in a parallelogram, the question is, "how many interior angles does a parallelogram have?"
Answered by Penny Nom.
Water usage in Ames 2014-08-29
From Abigail:
The City of Ames water treatment plant treats 7 million gallons of water per day on average to meet water demands. Hypothetically, if water is withdrawn from a groundwater system with an area of 51.6 square miles (approximate area of Ames and surrounding area), what is the depth of water in inches that would have to be added to the groundwater system annually to replace the water that is withdrawn by the city?
Answered by Penny Nom.
Three collinear points 2014-08-28
From jhanavi:
p,q,r are three collinear points.p and q are(3,4) and (7,7) respectively and PR is equal to 10 units.find coordinates of R
Answered by Penny Nom.
Logarithms 2014-08-28
From effaryna:
how logarithms is applied in everyday life?
Answered by Penny Nom.
Using a bucket to fill a tub 2014-08-27
From Charlotte:
A bathtub needs to be filled with water. To fill the tub, a bucket needs to be filled then dumped into the tub. If the bucket is a cylinder with a radius of 6 in. and a height of 12 in, how many buckets will it take to fill the 5 ft x 3 ft x 3 ft tub.
Answered by Penny Nom.
Cutting a round cake so that it doesn't dry out 2014-08-26
From James:
I'm wondering if there's a simple way to calculate the area between two parallel chords of a circle equidistant from its diameter, or if I have the area, to find the distance between the two chords.
Here's my "problem". You may have heard of the way of cutting a round cake so that it doesn't dry out - make two parallel cuts (chords) the length of the cake, take the middle piece, then push the two pieces together.
So I know the area of a 12" cake, and I want say, exactly an eighth of the cake. How wide do I cut the centre piece? Now to get even more difficult, the next day I want another eighth from the centre. How wide do I cut the next pieces, and so on...? Thanks, James

Answered by Harley Weston.
A car passing a bus 2014-08-24
From Athish:
the driver of the car is travelling at 36 km/hr and spots a bus 80 m ahead of him after 1 hr the bus is 120 m behind the car what is the speed of the bus
Answered by Penny Nom.
The inverse of f(x) = x^2 - x 2014-08-22
From Tyler:
Find the Inverse function of:
f(x) = x^2 - x

Answered by Robert Dawson.
The perimeter of a triangle 2014-08-21
From Phyllis:
What is the perimeter of a five acre triangle with one side being 250 feet and the second side would be at a 90 degree angle.
Thank you.

Answered by Penny Nom.
Filling three holes with stones 2014-08-20
From mark:
how many tonnes of hardcore/crushed stone would it take to fill 1 hole 9ft diameter 5ft deep and 2 holes both 3ft diameter and 5ft deep
Answered by Penny Nom.
Revisiting 8 golfers in two foursomes 2014-08-19
From steve:

I noticed you had an answer on how can you put 8 golfers in even foursomes over 7 games so that everyone plays with everyone equally. However the formula showed the following sequence that was used but did not go past the second day. Can you change the 0s and 1s into the numbers 1 to 8 instead. Here is what you have written:
Day 0 : (0, 0, 0, 0, 1, 1, 1, 1)
Day 1 : (0, 0, 1, 1, 0, 0, 1, 1)
Day 2 : (0, 1, 0, 1, 0, 1, 0, 1)
Day 3 : (0, 1, 1, 0, 1, 0, 0, 1)
Day 4 : (0, 0, 1, 1, 1, 1, 0, 0)
Day 5 : (0, 1, 0, 1, 1, 0, 1, 0)
Day 6 : (0, 1, 1, 0, 0, 1, 1, 0)

Thank you so much for your anticipated help.

Steve


Answered by Harley Weston.
A barge of triangular cross section 2014-08-18
From tushar:
a barge of triangular cross section is 20m long 12 m wide and 6m deep.its floats in SW at a draft if 4m find its displacement
Answered by Penny Nom.
4 rounds of golf as three foursomes 2014-08-18
From Christopher:
For our golf trip, we will be playing 4 rounds of golf as three foursomes. We would like to have each person play with everyone at least once. Is this possible?
Answered by Victoria West.
A price increase and a consumption decrease 2014-08-16
From sujan:
If the price of petrol increases by 25% and Rajesh intends to spend only 15% more on petrol then by how much % should he reduce the quantity of petrol he buys?
Answered by Penny Nom.
The equation of a circle 2014-08-14
From jennifer:
hi there My name is Jennifer and residing in Denmark. I am a student and I wrote to you because i am having trouble in finding out the equation for the circle using (x-a)^2 + (y-b)^2 =3D r^2.The diameter of this circle is d=3D 44,514 cm. I have attached a drawing of my problem..thanks
Answered by Penny Nom.
What percentage of 317 million is 1.2 million? 2014-08-13
From Danielle:
I would like to know what percentage of 317 million is 1.2 million.
Answered by Tyler Wood.
Distance, speed and time 2014-08-13
From abdel:
Mac walked to a park from the college at 5 km/h. 10 minutes later, Steve started riding his bike at 15 km/h to the same park to meet Mac. They arrive at the same time at the park. How far is the park from the college?
Answered by Tyler Wood.
1/3 of $320 2014-08-13
From Student:
Grade:5
Please help I got tutor for selective and this question is really bugging me a lot what is 1/3 of $320?

plez answer quick before I fail :(

Answered by Tyler Wood.
Speed, distance, time 2014-08-13
From Aarti:
a theif running at 8 km/hr is chased by a policeman whose speed is 10km/hr.if the thief is 100 m ahead the policeman then what will b time required for the policeman to catch the thief?
Answered by Tyler Wood.
How do you convert square mm to square cm? 2014-08-13
From David:
How do you convert square mm to square cm?
Answered by Tyler Wood.
Ratios ond percents 2014-08-13
From aswathi:
if the ratio of cost price and selling price of an article is be as 10:11,the percentage of profit is
Answered by Tyler Wood.
Golf for 10 2014-08-12
From Fred:
We have 10 golfers playing 4 rounds: one 4-some and two 3-somes each round. Can you suggest the best distribution of players?
Answered by Victoria West.
Golf for 15 2014-08-11
From Brian:
I am trying to arrange 5 rounds of golf for 15 golfers. We will play 5 in a group, 3 groups per round, 5 rounds. I would like everyone to play with everyone else. Secondary objective would be for no one to play with anyone else more than 2 times.

Thank you.

Answered by Victoria West.
Multiplication in base five 2014-08-07
From Alise:
Hi Maths Central!

I was wondering if you could help me with multiplying in base 5. I have read a question previously answered by you in regards to this but got fairly confused by it and was hoping you could help me with my question.

My question is: Multiply 1422 base 5 by 21 base 5 keeping these numbers and answer in base 5.

Would you also be able to explain how to get to the answer?

Thanks!

Answered by Penny Nom.
4821x14y is an 8-digit number divisible by 72 2014-08-06
From RAYA:
if 4821x14y is an 8-digit number divisible by 72. How many values can x and y take?
Answered by Penny Nom.
A chord and an arc of a circle 2014-08-06
From Luis:
Hello I am trying to figure out how to get chord lengths of quarter points for a circle. I work with large diameter circles and I need to be able to find chord length from 0 degrees to 90 degrees, 0 degrees to 270 degrees, 270 degrees to 180 degrees and 90 degrees to 180 degrees. Can you please use 100ft. diameter as example and work out the problem. I'm sorry if I use wrong terminology, I'm really bad at math . Thank you in advance for your time and help I really appreciate it.
Answered by Harley Weston.
The area of a quadrilateral 2014-08-06
From Rahul:
find the area of the quadrilateral whose side measure9cm,40cm,28cm,15cm and in which the angle between the first 2 sides is a right angle
Answered by Penny Nom.
The area of a kite 2014-08-04
From Janis:
How do you calculate the area of a kite with the diagonals 24cm and 48cm?
Answered by Chris Fisher and Penny Nom.
The dimensions of a rectangle 2014-08-03
From Jamaica:
if the perimeter of a rectangle is 30m and its area is 56 m2.find its length and width?
Answered by Penny Nom.
A concrete driveway 2014-08-03
From Jonathan:
How many 90 pound bags of concrete will fill in a 3 inch deep, 20 foot long, 12 feet wide driveway?
Answered by Harley Weston.
What is the average of first 100 even numbers? 2014-08-02
From Faizan:
What is the average of first 100 even numbers?
Answered by Chris Fisher.
A 6 team sports schedule 2014-08-02
From Daniela:
Hello,

My husband and I are volunteering at our church's Jrs camp and we were given the task of making the schedule for sports. There will be 6 teams and a total of 3 games for two days. We would like for every team to play each other but we cannot figure it out. Pls help!

Thanks.

Answered by Victoria West.
A word problem with fractions 2014-08-01
From nathanielcabalan:
The denominator of a fraction is one more than the numerator. If the numerator is increased by three, the resulting fraction is one more than the original fractional. Find the original fraction.
Answered by Penny Nom.
Dealing cards in the ratio of 4:3:6 2014-07-31
From aneeqa:
Maria, Sofia and Diana shared some cards in the ratio of 4 : 3 : 6. Diana received 14 more cards than Maria. How many cards did Sofia receive?
Answered by Penny Nom.
The sum of the first 50 terms of an arithmetic progression 2014-07-26
From Joshua:
Hello ...my is Joshua...I'm a grade 11 student...I got a question

Calculate the sum of the first 50 terms of an arithmetic progression: 112:98:84

Answered by Penny Nom.
A word problem concerning averages 2014-07-26
From Bernie:
The average weight of a team of children is 50kg, Todd who weighs 56 kg then joins the team. The average weight of the new team is 51. How many children in the original team?
Answered by Penny Nom.
An arc subtended at the center of the Earth 2014-07-20
From Abhinav:
Meerut is 60 km from Delhi. Find the nearest second the angle subtended at the center of the earth by the arc joining these two points,earth being regarded as a sphere of 5940 km radius.
Answered by Penny Nom.
60% as much as $30. 2014-07-18
From Kenneth:
Question from Kenneth:

Hello:

Do you know why some "as...as" phrases indicate multiplication?

For example, ? is 60% as much as $30. This is equivalent to 60% X $30 = $18. How does this make sense?

I saw this example in an old textbook on business mathematics, but the author did not explain why it is equivalent to multiplication.

I thank you for your reply.

Answered by Robert Dawson.
Selecting a meal at a school cafeteria 2014-07-18
From Gil:
A school cafeteria offers 2 main entrees, 3 fruits, 4 vegetables, and 3 drinks. If a plate consists of 1 entree, 2 vegetables, 1 fruit, and 1 drink, how many different plates can a cafeteria manager make? Please explain how you derived at answer. Thank you
Answered by Penny Nom.
Expand and simplify [x-3][x+3] 2014-07-16
From symion:
Expand and simplify [x-3][x+3]
Answered by Penny Nom.
An octagon around a tree 2014-07-16
From floyd:
I want to build an octagon 4 feet from base of tree from 4x4's. What length do I cut my pieces
Answered by Penny Nom.
Solve sin3x = cos2x 2014-07-14
From Emanuel:
If sin3x=cos2x, find the value of x when x<0<90'
Answered by Penny Nom.
16 golfers over 15 weeks 2014-07-11
From Steve:
I need a schedule for 16 golfers over 15 weeks, where each golfer is paired with a different golfer each week and plays 4 matches per week against 4 different pairs (each pair does not have to play each week)
Answered by Penny Nom.
Brandon went shopping - working backwards 2014-07-11
From Sindy:
Brandon went shopping & spent 1/4 of his money on shoes & 1/5 of the remainder on a new wallet. He then spent $60 on a pair of jeans. If he had $60 left, how much did Brandon start with?
Answered by Penny Nom.
Sharing in the ratio of of 2:3:5 2014-07-11
From Muzdalfah:
Amount of Tsh 12,000 is to be shared among John,Hidaya and sabrina in the ratio of of 2:3:5 respectivly.How will each get?
Answered by Penny Nom.
A 14 team golf league 2014-07-11
From Pat:
We have a 14 team golf league that plays a 16 week schedule. Playing once per week, I need a schedule where each team plays every other team at least one time.
Answered by Victoria West.
Fencing around a 6 sided property 2014-07-10
From Annette:
Hi, I've tried every way to figure this out and looked at your other acreage questions and still don't have an answer. It's my Birthday today and it would make me so happy to figure this out. I have this area I want fenced on my property and need to figure out how many acres it is to know if this guy is charging fare price for fencing.
It has 6 sides to it and measured in feet the sizes are: 1400 ft long
807 ft long
1060 ft long
300 ft long
310 ft long
400 ft long

Hope you can help me.
Thanks.
Annette

Answered by Penny Nom.
A 5 sided lot 2014-07-10
From mia:
have the feet numbers of three sides, but the forth side is in a "V" so it has two figures. Question: can i add the two figures of the "v" together to get one figure, so then I would have the figures for all four sides.
Answered by Harley Weston.
4/9 of a set of story books cost Rs 630. 2014-07-09
From YASIN:
If 4/9 of a set of story books cost Rs 630. What will the rest of the set cost?
Answered by Penny Nom.
A ladder against a wall 2014-07-09
From thabo:
A ladder 6.5m long,leans against a wall so that the top of the ladder is 4.8m from the ground.what is the angle of elevation of the ladder to the top of the wall
Answered by Penny Nom.
67 cubic yards in cubic metres 2014-07-09
From gavin:
Convert 67 cu yards into cu metres
Answered by Penny Nom.
A rotation schedule for 14 teams 2014-07-08
From Daniel:
I am organizing team activities for a summer camp. We have 14 teams and 7 rotations and 7 different games. every team will play a different game each rotation. Where I am having trouble is I would like each team to play a different team each rotation without a repeat. Is that possible? if so what is the formula?
Answered by Victoria West.
14 golfers, 7 men and 7 women 2014-07-06
From John:
I have to schedule 14 golfers, 7 men and 7 women, into 4 teams each day, playing for 3 days. So each player plays with as many different players as possible for 3 games.
Answered by Victoria West.
An antenna is atop a building 2014-07-05
From Andrew:
If an antenna is atop a building 70 feet tall and the antenna has a beamwidth of 30 degrees how far from the building does the beam first touch the ground?
Answered by Penny Nom.
The method of elimination 2014-07-05
From leo:
please explain how can i solve this problem

3x-6y=-38
6x-9y=44

using elimination and simultaneous method thank you :)

Answered by Penny Nom.
Quarters 2014-07-04
From kamal:
how many quarters in the sum of 8 and 12 ?
Answered by Penny Nom.
Sum of 22, product of 125 2014-07-03
From marj:
find two real numbers whose sum is 22 and whose product is 125.
Answered by Paul Betts, Robert Dawson and Penny Nom.
The width of a rectangle 2014-07-02
From john:
if the area of a rectangular field is 90 sq. m and its length its is 19 m find its width
Answered by Penny Nom.
Covering a 12 inch by 12 inch square hole 2014-07-02
From Patricia:
I am putting in a new bathroom fan. I am wondering if a new light with a 15 inch diameter will cover the existing square hole which is 12 by 12 inches? If the existing hole is 11 1/2 by 11 1/2 inches?

Also, if the 15 inch diameter does not cover the 12 by 12 hole, what size diameter would?

Thank you.

Answered by Penny Nom.
A six digit number 2014-06-30
From anupam:
hi,
my daughter asking a solution for the below question, kindly help.

Write the smallest 6 digit number wit digits ( 2,4,3,0,5,7).

plz this is an urgent requirement.

regards,
anupam

Answered by Penny Nom.
Buying shoes on sale 2014-06-30
From Willa:
So, I have this question from my summer packet: "Gwen buys 3 identical pairs of shoes at store a. She pays $110.25 after the discount what is the regular price of each pair? ( 40% off)"
Answered by Penny Nom.
Angular speed 2014-06-29
From andrea:
a wheel having a radius of 10cm rotates such that the linear speed at its rim is 30mls. what is the angular speed of the wheel in rpm?
Answered by Penny Nom.
Differentiate ln[x(2x-4)^1/2] 2014-06-28
From Igwe:
If y=In[x(2x-4)^1/2],find dy/dx at x=3
Answered by Penny Nom.
A triangle on the surface of the Earth 2014-06-26
From Christine:
A, B and C are three towns, the bearing of B and C from A being 310 degrees and 220 degrees, and their distances from A are 510km and 700km respectively. Find the bearing of B from C to the nearest minute.
Answered by Robert Dawson.
50+9-13 multiplied by 2= 2014-06-25
From Adrian:
50+9-13 multiplied by 2=
Answered by Penny Nom.
The largest odd number using the digits 08672 2014-06-24
From audrey:
what is a 5 digit greatest odd number out of this given digits? 08672
Answered by Robert Dawson.
12 golfers 2014-06-23
From Derek:
I have a golf group that is set up as follows.12 players broken into 2 teams of 6.We play as a 4 ball ie 2 from each group.I am looking for a formular to have the 2 players from each group not play with each other again & also both of the 2 in each group not play with others in the other group more than once.I don't believe it is possible,so will accept as little duplication as possible-many thanks-Derek
Answered by Victoria West.
An oval pool 2014-06-21
From steve:
I have a 16' x 28' oval pool that is buried 24" deep inground. The dig site is dug 2' wider all the way around the pool. I need to back fill this area with stone. I want to fill this area with 6 to 8" of stone. How many tons of stone will this take?

Thanks you
Steve

Answered by Penny Nom.
How can eight eights be 1000? 2014-06-20
From Aamir:
The digit 8 if we add it 8 time in it the answer should be equal to 1000.it may possible.i.e., 8+8+8+8+8+8+8+8=1000
Answered by Penny Nom.
Simultaneous equations 2014-06-20
From rana:
solve the simultaneous equations
a)3x=7y
12y=5x-1

Answered by Penny Nom.
The ratio of 1:1:2 2014-06-20
From FREDERICK:
3 girls shared some hair ribbons in the ratio of 1:1:2 what is the total number of hair ribbons if the third girl got 14 ribbons.
Answered by prnny.
How many kilometers to a longitudinal degree? 2014-06-19
From cherrielyn:
Assuming that earth is a sphere of radius 6380 km, what is the difference in the latitudes of two cities 270 miles apart positioned on the same meridian?

Thank you in advanced po! :)

Answered by Robert Dawson.
A reversed curved on a railroad track 2014-06-19
From cherrielyn:
Assuming that earth is a sphere of radius 6380 km, what is the difference in the latitudes of two cities 270 miles apart positioned on the same meridian?

Thank you in advanced po! :)

Answered by Penny Nom.
The number of standard deviations 2014-06-15
From Dawn:
Suppose that, at a certain college, the average weight of all male students is 160 pounds with a standard deviation of 30 pounds. A certain male student weighs 145 pounds. Determine how many SD's his weight is above or below average.
Answered by Penny Nom.
6 character strings using 1, 5 and 9 2014-06-15
From Kevin:
How many 6 digit combinations (i.e., 159159) can be made from 3 different numbers (i.e., 1,5, and 9)? The numbers will obviously have to repeat. A link to a calculator that could list all the combinations would be helpful. I've come across these sites: http://textmechanic.com/Permutation-Generator.html, and http://textmechanic.com/Combination-Generator.html , but am not sure how to use them for my specific case. Thanks.
Answered by Penny Nom.
Profit 2014-06-14
From roudha:
find the profit of one item if it was bought for AED 180 and sold for AED 275. assume that the additional costs are AED 25 .
Answered by Penny Nom.
Two regression lines 2014-06-14
From catherine:
Given a set of data values ,we can get two regression lines .Explain.
Answered by Robert Dawson and Penny Nom.
A model of the sun and the Earth 2014-06-14
From Lynn:
There is a model of the sun that is 2 1/2 inches in diameter. This is the only clue we have! How far away is the earth from this model?
Answered by Penny Nom.
A small solid silver pyramid 2014-06-13
From Jenesis:
For Awards Night at Baddeck High School, the math club is designing small solid silver pyramids.The base of the pyramids will be a 2 in by 2 in square. The pyramids should not weigh more than 2.5 pounds. One cubic foot of silver weighs 655 pounds. What is the maximum height of the pyramids?
Answered by Penny Nom.
The area of a circle of circumference 32.69 meters 2014-06-11
From coco:
Find the area of a circle with a circumference of 32.69 meters.
Answered by Penny Nom.
Forming a cylinder from a square 2014-06-08
From kalyani:
the curved surface of a cylinder is a square of diagonal 2*square root of 2. What is the area of the base of the cylinder?
Answered by Penny Nom.
Another conditional probability problem 2014-06-08
From PAVITHRA:
Two dice are thrown. What is the probability that sum of the numbers appearing on the die is eleven, if five is appear on the first die
Answered by Penny Nom.
Bags of sand 2014-06-06
From Robert:
We have a section that is 20ft long by 14ft wide and 4inches deep, the bags of sand are .5 cubic ft. How many bags of sand do we need to fill this space evenly.
Answered by Penny Nom.
Factorials 2014-06-06
From penny:
What is factorial? For eg. Like 2!, 3! 4! Etc.
Answered by Penny Nom.
20 teams and 10 competition stations 2014-06-04
From Joel:
I have 20 teams. There are 10 competition stations. Each station will accommodate exactly 2 teams to compete with each other at a time.

Each of the 20 teams needs to compete at each of the 10 stations exactly one time.

Here's the catch I cannot solve: how to schedule it so that each team plays EVERY OTHER TEAM once and only once, while never repeating a station.

Answered by Victoria West.
10 golfers, playing 7 rounds in 2 x 3balls and 1 x 4ball 2014-06-04
From adrian:
Hi, We are off to Scotland on our yearly golfing trip soon. Question is we have 10 golfers, playing 7 rounds in 2 x 3balls and 1 x 4ball. I would like to ensure that each golfer plays with the other guys an equal amount of times, guess 3ish? and we share the amount of times each player plays in the 4ball. Hope you can help?
Answered by Victoria West.
How do we use logarithms in our daily life 2014-06-01
From ss:
how do we use logarithms in our dailylife
Answered by Penny Nom.
6 inches of dirt in a baseball field 2014-06-01
From Mary:
The baseball field is 20,000 Square feet, 6 inched deep I need to know how many cubic yards of dirt this will generate.
Answered by Penny Nom.
How do I make fractions into decimals? 2014-05-31
From jay:
Hi,
I wanted to know how do I make fractions into decimals example 1 3/8?

Answered by Penny Nom.
An equilateral triangle with vertices in 3 parallel planes 2014-05-31
From prajay:
How to construct an Equilateral Triangle whose vertices lie on three parallel lines, if the distances of two lines are 'a' and 'b' units from the middle line.What is the length of the side of the Equilateral Triangle ?
Answered by Chris Fisher.
A word problem with fractions 2014-05-30
From shadab:
A container of milk is 4/5 full. When 10l milk is poured into it, the container becomes 9/10 full. What is the capacity of the container ?
Answered by Penny Nom.
A rotating schedule for 9 individuals 2014-05-29
From Josh:
I need to set up a rotating schedule for 9 individuals. The individuals will be pairing each week in groups of two. Thus, every week there will be 4 groups of two individuals and one individual not paired with anyone (i.e. a "bye week"). The rotating schedule should not repeat any pairing and it will continue until each individual has been paired with every other individual once.
Thank you

Answered by Victoria West.
The combination of 6 numbers from 1 to 355 that gives us 360 2014-05-29
From Ion:
Hi,
My name is Ion and I am trying to find the number of combinations of 6 numbers (angles) that would sum to 360 (degrees).

Thank you!

Answered by Robert Dawson.
A word problem with fractions 2014-05-23
From Tanzeela:
There are 1200 pupils in a school. 2/3 of them are girls. 1/4 of the boys are overweight. How many boys are overweight?
Answered by Penny Nom.
Overlapping sets 2014-05-23
From daniel:
motors inc manufactured 325 cars with automatic transmission,216 with power steering ,and 89 with both these options. How cars were manufactured if every car has at least one option?
Answered by Penny Nom.
The volume of a wedge 2014-05-21
From steve:
I need to figure the volume of a wedge / right triangle, the dimensions of the right triangle is L1(10'-5"), L2 (10'-6"), H (14'-9.5") height of L1 is 0'-0" height at intersect L2/H is 3'-3"
Answered by Penny Nom.
The volume of hexagonal pyramid and hexagonal prism 2014-05-18
From visshwam:
how to find volume of hexagonal pyramid and hexagonal prism? my measurements are each side of pyramid's triangle is 1"x2"x2".

hexagon prism is 2"x1" each side

Answered by Penny Nom.
What is the speed of the buses? 2014-05-18
From musliu:
Two buses leave a bus station and travel in opposite direction from that same starting point.if the speed of one is twice the speed of the other and they are 240km apart at the end of 1h, what is the speed of the buses?
Answered by Penny Nom.
The height of a building 2014-05-17
From Jim:
If I'm 150 ft. from the base of a building and the top of the building is approx. at a 75 degree angle, how do you calculate the height?
Answered by Penny Nom.
14 golfers for 13 weeks 2014-05-17
From Judi:
I want to schedule each of my 14 golfers to play each of the other girls one time during a 13 week period. We would golf in foursomes , threesomes or twosomes to make this happen. Can you send me a grid that would do this scheduling? I'm at a loss as to how to do it!!
Answered by Victoria West.
The weight of salt in a basket 2014-05-17
From Sumit:
I want to determine how many kg of salt or XYZ thing can be filled in a basket
Length = 4.5"
Breadth = 5"
Height = 6"

Even its formulae

is kg quantity can be different for semi solid thing

Answered by Penny Nom.
The equation of a line 2014-05-16
From Michael:
Find the equation of a line that passes through (2,-1); the sum of the x- and y-intercepts is 2. (There are two answers)
Answered by Penny Nom.
A hexagon with different side lengths 2014-05-16
From Grace:
Sorry if this is a simple question, but I can't seem to understand how to solve it. I am Trying to find the area of a hexagon with measurements 6x7x6x6x7x6, or 2 sets of opposing sides with 6, and one set with 7. Thank you.
Answered by Penny Nom.
Golf for 14 players over 12 weeks 2014-05-16
From Judi:
How would I develop a playing schedule using foursomes and one twosome for 14 players who will play 12 weeks and each person would play all but one of the others?
Answered by Victoria West.
Three digit numbers 2014-05-15
From Mudassir:
how many 3 digits numbers which at least one digit is 2 ?
Answered by Penny Nom.
A problem with numbers 2014-05-14
From Justina:
Okay so I don't understand how to equal this equation to 10 using bedmas. I've been stuck on it for a few days now. Is there different ways you can show me Using these same numbers?

5 2 4 3 1 = 10

Help! Thanks.

Answered by Robert Dawson and Penny Nom.
18 golfers for 5 rounds with a teaching Pro 2014-05-14
From Maree:
We are taking 18 golfers on Tour with a teaching Pro. There are 5 rounds of golf and we want everyone to play with the Pro once, but everyone else to play with as many different people as possible
Answered by Victoria West.
Eleven guys on a fishing trip 2014-05-13
From Mark:
Eleven guys are going on a fishing trip and want to rotate so everyone fishes with the other guys with the fewest number of repeats. They want to fish in groups of two with one fishing alone for three and a half days so will rotate seven times. Is there a combination that works and what is it?
Answered by Victoria West.
A circle a square and a rectngle 2014-05-12
From mazhar:
suppose the length and breadth of the rectangle are 5 cm and 10 cm respectively and M is a point along the corner of the circle. what is the radius of the circle?(diagram is given..but i didn't mention it..actually the diagram looks like a circle inscribed in a square and the right bottom corner one rectangle will be given ,it is touches to circle at a point M that I've already mentioned and the dimensions of that rectangle also I've mentioned) please help me out..
Answered by Penny Nom.
Travelling upstream and downstream 2014-05-12
From Mohanad:
Howie Sorkin can travel 8 miles upstream in the same time it takes him to go 12 miles downstream. His boat goes 15 mph in still water. What is the rate of the current?
Answered by Penny Nom.
A 12 week poker tournament 2014-05-12
From Jamie:
Looking to schedule a 12 week poker tournament with 18 players ...playing 2 separate 9 person tables...I'm looking to have a balanced schedule where everyone player with each other an equal amount of time
Answered by Victoria West.
Mary's height as a percentage of Michael's height 2014-05-11
From Lauren:
Mary is 1.4m tall and her brother Michael is 1.2m tall.
Express Mary's height as a percentage of her brother's.

Answered by Penny Nom.
A piecewise graph 2014-05-10
From Zoe:
Lightning Energy charges residential users for each unit of electrical energy bought from them each quarter, according to the scale below:
0-500 units cost 17 cents per unit
500-1500 units cost $85 plus 10 cents for each unit in the excess of 500
1500 or more units cost $185 plus 9 cents for each unit in excess of 1500
Sketch a graph showing the charge C as a function of U for up to 2000 electricity units

Answered by Penny Nom.
The length of a shadow 2014-05-09
From vijay:
A girl of height 80 cm is running away from the base of a lamp-post at a speed of 2 m/s. If the lamp is 4 m above the ground, find the length of her shadow after 5 seconds.
Answered by Penny Nom.
Percentage change 2014-05-09
From hi:
the hw club had 46 members in sept. in april, the club had 24 members. what was the percent of change in the hw club's membership from sept. to apan increase or decrease in membership? ril? what is
Answered by Penny Nom.
A question concerning two lines 2014-05-09
From Hela:
The equation of the line L is 6x+5y=3, and the equation of line Q is 5x-6y=0, which statement below about the line is true?
A) same y intercept
B)parallel
C) Same x intercept
D)perpendicular

Answered by Penny Nom.
x - 2 Sin[x] = 0 2014-05-08
From chanmy:
please help me to sole this equation x - 2 Sin[x] = 0,thank you
Answered by Penny Nom.
How many boards did the carpenter start with? 2014-05-08
From Yanly:
A carpenter has several boards of equal length. he cuts 3/5 of each board. After cutting the boards, the carpenter notices that he has enough pieces left over to make up the same length as 4 of the original boards. How many boards did the carpenter start with?
Answered by Penny Nom.
A schedule for 2 teams of 10 2014-05-07
From John:
How can I set up a schedule for 2 teams of 10 on a team to play each individually against each other over a 10 day span at 10 different course with 10 different start times each day. I was looking to not repeat any competition. As an example, Team A would consist of players 1-10, Team B would consist of players 11-20. I would want to have 10 start times a day for 10 days where a member of team A plays a member of team B each day without repeating any matches and any of the same courses and not repeating any of the same start times. Any help in this would be GREATLY appreciated!!!!
Answered by Victoria West.
A 5-person golf flight 2014-05-05
From Jeremy:
can you have a 5-person golf flight and play only 3 matches so that one person plays one match each?
Answered by Victoria West.
Golf for 8 2014-05-05
From Ivan:
We have an eight member golf team. We field one foursome each week for 16 weeks of league play. How do I roate the eight members so each team member plays with each team member and all play an approximately equal number of times?
Answered by Victoria West.
4 golfers in twosomes 2014-05-04
From Lori:
4 golfers want to play as 2 somes every week, but rotate the 2 players so we all play together With each other evenly thru out the summer
Answered by Victoria West.
19 acres by 12 feet deep 2014-05-04
From Bernie:
How many cubic yards of dirt is in 19 acres if you dig down 12ft ?
Answered by Penny Nom.
Golf :15 players over 4 days 2014-05-02
From michael:
We are playing with 15 players over 4 days. We plan to have 3 people in each group. A total of 5 groups with 3 players each. Can I arrange for each player to play with other players only 1 time?
Answered by Victoria West.
1[1-√2(order of surd is 4)] 2014-05-02
From Anoushka:
if t=1[1-√2(order of surd is 4)] , then t=?
Answered by Penny Nom.
Surface area 2014-05-02
From vijay:
If a square paper of side 25 cm is rolled to form a cylinder, then its curved surface area is
Answered by Penny Nom.
11 golfers going on a golf trip for 4 rounds 2014-05-01
From David:
I have 11 golfers going on a golf trip for 4 rounds of golf. I want to make sure that everyone gets a chance to play with everyone at least once but not more than twice. Also, as we are n = 11, we will be composed of 3-4-4 everyday. I am trying to ensure that as few as people as possible play in the group of 3 (golf seems to be more enjoyable for whatever reason in foursomes). i have tried 3 differemt times and can seem to figure it out. Can you assist?
Answered by Victoria West.
2 teams of six playing each other 4 times 2014-05-01
From Steve:
I have 2 teams of six (Team A & B)- playing each other 4 times.

Is it possible to have a player from Team A play with a different partner from Team A for each of the 4 rounds, and likewise for Team B. Whilst no player from either team plays an opponent more than twice during the 4 rounds?

Answered by Victoria West.
The distributive property 2014-04-30
From Madison:
3a(7b+6c). The directions are: use the distributive property to rewrite the expressio .
Answered by Penny Nom.
If x+y+z=1 then x^2 + y^2 + z^2 = ? 2014-04-30
From Nitin:
If x+y+z=1 then x^2 +y^2+z^2 = ? ?
Answered by Robert Dawson.
A cone of vision 2014-04-29
From David:
It is known that a fish in water looking up has a 97 degree "cone" of vision that sees "through" the surface of the water. If a fish lies 4 inches below the surface, the cone forms a window (circle) smaller than if a fish lies 8 inches below the surface. What is the ratio of inches of depth to the radius of the circle on the surface that is its visual window?
Answered by Penny Nom.
Profit and loss 2014-04-29
From Anoushka:
A man sells two tables of the same price. On one he makes a profit of 10 percent and on the other he suffers a loss of 10 percent.Find his loss or gain percent on the whole transaction.
Answered by Robert Dawson.
2cos^2x+cosx=sin^2x 2014-04-28
From MaryBeth:
find all solutions of the following equation in the interval [0,pi] 2cos^x+cosx=sin^2x
Answered by Robert Dawson.
Fractions and units 2014-04-28
From Aaron:
I can't do this math problem. please help. Find 200m over 1 min times 60 min over 1 hr times 1 km over 1000 m. the choices are a. 300 km/hr b. 12 km/hr c. 300 m/hr and d. 12 m/hr
Answered by Penny Nom.
2 cars driving towards each other 2014-04-27
From Joakim:
2 cars driving towards eachother , the distance between them is 162km. they meet after 2 hours. car A is driving with 4/5 of car Bs speed. what is the speed of each car...
Answered by Penny Nom.
A triangular chicken pen 2014-04-27
From Cierra:
Margaret has two lengths of fence, 20 meters and 24 meters, for two sides of a triangular chicken pen. The third side will be on the north side of the barn. One fence length makes a 75 angle with the barn. How many different pens can she build if one fence is attached at the corner of the barn? What are all the possible lengths for the barn side of the pen?

Not sure what they are asking here... please show step by step what to do! Thank you so much!

Answered by Penny Nom.
The volume and radius of a sphere 2014-04-27
From grace:
How do you find the radius of a sphere when all you know is the volume?
Answered by Penny Nom.
The derivative of sin(x) 2014-04-26
From Lucky:
f(x)=Sin(x), by first principle its f'(x)...show me how to solve such problem.
Answered by Penny Nom.
A schedule for 9 teams on 3 fields for 18 days 2014-04-25
From Scott:
I need to schedule 9 teams on 3 fields for 18 days with no buys. Two teams play while other practices in field(little guys). Two fields have backstops and other is open field. Would like to have even time on each diamond if possible. Thank you
Answered by Victoria West.
Solve for theta 2014-04-25
From ALASTAIR:
Hi, The question asks Solve for 'theta' cos2theta=sintheta x costheta. Substituting for cos2th either 1-2sin^2th or 2cos^2th does not give an equation in either sine or cosine alone how do I solve this please?
Answered by Penny Nom.
An octagonal pad 2014-04-25
From George:
Hi, I need to pour a cement pad in the shape of an octagon that allows for 12" of clearance around the tank I will be putting on it. The tank has a radius of 16'.
Answered by Penny Nom.
A trig problem 2014-04-25
From srishti:
Consider the points P= (-sin(a-b),-cosa), Q=(cos(a-b),sina), R=(cos(a-b+c),sin(a-c), where 0
Answered by Chris Fisher.
What was the selling price? 2014-04-25
From Con:
Apple built 40 32GB wifi iPads, gave away two in a contest, and sold the rest at two times the manufacturing price. If the company's total profit was $10,782, what is the selling price of one of these iPads?
Answered by Penny Nom.
What time was it when joe's brother passed him? 2014-04-25
From Nathan:
joe left home in his bike at 10:00 am, traveling 21 km/h. At noon, his brother set out after him on his motorcycle, following the same route. if the motorcycle traveled at 63 km/h, what time was it when joe's brother passed him?
Answered by Penny Nom.
A quadratic equation given the roots 2014-04-23
From Sarah:
How do you find the quadratic formula when you're given just the roots ... X=-3 X= 1/3 Thanks !
Answered by Robert Dawson.
Two 9 hole golf leagues 2014-04-23
From Sally:
I need help scheduling two 9 hole leagues. Here are the variables:
- Leagues alternate each week starting on the front and back
- League A starts at 4:30 with 7 groups and League B starts at 5:15 with 8 groups (all use carts and must be teed off by 5:30)
- Regular play must continue, customers who have started before league play begins have preference to continue their round whether they are playing 9 or 18 holes.
Thank you!!!

Answered by Victoria West.
Golf for 6 2014-04-21
From barbara:
We are a group of 6 golfers. We play in groups of 3 for 5 days. How can I arrange the groups that everybody plays with everybody else at least once? Thanks.
Answered by Victoria West.
Golf with 3 teams of 20 2014-04-21
From Joshua:
Thank in advance for this great service

Golf - new - 3 teams of 20 - to create 20 unique groups of 3

For example use 3 teams of 3

1a 2a 3a
1b 2b 3b
1c 2c 3c

So groups are
1a 1b 1c
2a 2b 2c
3a 3b 3c

Groups can only have one a, one and one c - and that combo should be unique

Answered by Victoria West.
A 22 team golf league 2014-04-21
From Terry:
We have a team league at our local golf course. We have 22 teams, we would like it so that each team plays the other team only once. I have tried the scenario.
1,21;2,20;3,19;4,18;5,17;6,16;7,15;8,14;9,13;10,11;12,X X+1=1 scenario
2, 1;3,21;4,20,5,19,6,18;7,17;8,16;9,15;10,14;11,13;1,X
using formula from other post in your forums.

I can get all the possible playing arrangements. The big quandary is setting up the schedule so that each week, each team would start on a different hole.

I can get the first 11 weeks scheduled very easily, it is just trying to get the last 11 weeks scheduled?

Any help would be greatly appreciated.

Answered by Victoria West.
Golf League Schedule for 15 weeks and three flights 2014-04-21
From bigdog:
I need help setting up a 12 team (3 flights with 3 teams in each flight) 15 week league play schedule. Each team must play teams in there perspective flight twice during the 15 week season.
Answered by Victoria West.
A normal distribution problem 2014-04-19
From Melanie:
This is the question:
The lifetime of a certain type of car tire are normally distributed. The mean lifetime of a car tire is 40,000 miles with a standard deviation of 5,000 miles. Consider a sample of 10,000 tires. A) How many tires would you expect to last between 35,000 and 45,000 miles? b) How many tires would you expect to last between 30,000 and 40,000 miles? c) How many tires would you expect to last less than 40,000 miles? d)How many tires would you expect to last more than 50,000 miles? e) How many tires would you expect to last less then 25,000 miles? f) What tires would you want on your car and explain your reasoning Not at all sure that we've done any of this correctly and not sure how to determine how many tires will last less than 25,000 miles. Any help is appreciated.

Answered by Penny Nom.
An input output table 2014-04-19
From Stephanie:
I have an input output table with x/y filled out except one x and one y. I need help. How do I find X?
Answered by Penny Nom.
Simultaneous equations with fractions 2014-04-19
From Maryam:
I looked at your example of simultaneous equations with fractions and applied it to my question from an educate exam papers but I couldn't get it to work. The question is:

x/8 - y = -5/2
3x + y/3 = 13

Answered by Penny Nom.
Robyn and Shaun swim 2014-04-18
From kajinthan:
robyn swims four 35m lengths.shaun swims eight 15m widths. how much further does robyn swim?solve this maths
Answered by Penny Nom.
A frustum of a pyramid with a square base 2014-04-18
From tuba:
a pyramid has a base of 10 m and is 15 m high.what is the volume? if 6m is removed from top what is the volume of the remaining frustum?
Answered by Penny Nom.
Ratios 2014-04-18
From Kenneth:
Should ratios contain only whole numbers and not any fractional numbers?

For example, 8:1, 2:5 have whole numbers. The ratios 2.5:10 and 1:4.5 do not have just whole numbers entirely.

If it is incorrect to express a ratio with fractional numbers, why are complex fractions correct?

I thank you for your reply.

Answered by Harley Weston.
Ratios 2014-04-18
From Kenneth:
Should ratios contain only whole numbers and not any fractional numbers?

For example, 8:1, 2:5 have whole numbers. The ratios 2.5:10 and 1:4.5 do not have just whole numbers entirely.

If it is incorrect to express a ratio with fractional numbers, why are complex fractions correct?

I thank you for your reply.

Answered by Harley Weston.
A circle is divided into three sectors 2014-04-17
From atolagbe:
the area of a circle is 154cm square. it is divided into three sectors such that two of the sectors are equal in size and the third sector is three times the size of the other two put together. calculate the perimeter of the third sector. take pi=22/7?
Answered by Penny Nom.
What is this function? 2014-04-17
From Keta:
What is this function?
-12=-2
-6=-1
6=1
0=0

Answered by Penny Nom.
Barrels of oil 2014-04-16
From daryl:
Looking for an accurate number to use when calculating barrels per inch in a a tank with the following dimensions:
Nominal diameter - 15'-6", nominal height - 16ft, nominal capacity - 500 barrels. These are commonly referred to as 500x16 tanks.
Currently we are using 2.6 barrels per inch. We need 180 barrels for a full load so I'm trying to figure out how many total inches I need to load 180 bbl. This has been a matter of debate for some time. Thanks for your help.

Answered by Harley Weston.
The area bounded by the X-axis and y=x^(2)-4 from -5 to 0 2014-04-15
From Lexie:
Determine the area that is bounded by the following curve and the x-axis on the interval below. (Round your answer to three decimal places)

y=x^(2)-4, -5 ≤ x ≤ 0

The answer is 32.333 but I have no idea how to get there.

Answered by Penny Nom.
A tangent of the curve (x/a)^n+(y/b)^n =2 2014-04-15
From sudhir:
the equation of tangent of the curve (x/a)^n+(y/b)^n =2. at(a,b) is
Answered by Penny Nom.
A conditional probability problem 2014-04-13
From Chiluya:
Two fair dice are rolled. what is the probability that the number on the first die was at least as large as 4 given that the sum of the two dice was 8?
Answered by Penny Nom.
The cost before the sales tax 2014-04-13
From Juanda:
Hello,

I know the customer cost with tax and I know the sales tax.
How do I find out the customer cost prior to the added sales tax?

Thank you

Answered by Penny Nom.
A sand trench around a pool 2014-04-13
From steve:
How sand is needed to back fill a trench around a 24ft dia. pool that is 26" deep by 2ft wide. Making the outside dia. 26ft.

Thank You

Answered by Penny Nom.
Manipulating an equation 2014-04-12
From Paul:
S=4wl+2wh and solve for h
Answered by Penny Nom.
A slab of wet clay 2014-04-12
From Karen:
How many square feet ( at 1/4 inch thickness) are in 100 lbs. of wet clay?
Answered by Penny Nom.
A golf league with 20 players over 17 weeks 2014-04-12
From Chris:
I have a golf league 20 players and 17 weeks. We don't have teams so I just want to have everyone to play with each other the about same number of time and, hopefully, randomly distributed throughout the season. We have had situations in the past where two people play together for three weeks in a row and then not anymore for the rest of the season. From other posts, I see how to schedule the first 5 weeks without repeats but I cant figure out an algorithm to for the rest of the season. Thanks!
Answered by Victoria West.
Decimals,fractions and percentages 2014-04-11
From Frances:
Ask an expert to find out their real life usage of your topic... that is the question. meaning what is your real life usage of using decimals,fractions and percentages. This is all part of my math assignment to ask an expert real life usage... so please reply back as soon as possible
Answered by Penny Nom.
A golf league consisting of 14 two man teams 2014-04-10
From Kevin:
Hello, I need to make a schedule for a golf league consisting of 14 two man teams playing over the course of 20 weeks. I understand that each team will play at least once and I believe 7 teams will play each other twice over the course of the season. How would I generate this schedule. Thank you, Kevin Perry
Answered by Victoria West.
Converting to base 5 2014-04-10
From Usama:
Convert the numbers used in the following expressions into those of base-five and solve :
21+34-108+62
Convert the result so obtained into decimal system and thus check your answer?

Answered by Penny Nom.
The cosine of 2 theta 2014-04-10
From Kayla:
Find \cos 2 \theta if \sin \theta = \frac{11}{61}.
Answered by Robert Dawson.
How fast did Jessica grow? 2014-04-10
From jasmine:
when she was 14 jessica was 5 feet, 4inches tall . at 18 she is now 6 feet, 2inches tall .how fast did jessica grow during this time
Answered by Robert Dawson.
The surface area of a circular dome 2014-04-10
From Shafiqah:
Is this a dome's surface area formula??
{{2 π r h square units}}
Is the surface area of the floor for the dome is calculate too in this formula?

Thanks for answering. =)

Answered by Robert Dawson and Penny Nom.
Two rectangular prisms 2014-04-10
From hannah:
two rectangular prisms have a combined volume of 432 cubic feet Prism A has half the volume prism b has what are the volumes of prism a and prism
Answered by Penny Nom.
Two cones 2014-04-09
From c.j:
what is the length of the radius of the LARGER cone(the LARGER cone has a slant height of 15) when the SMALLER cone has a radius of 8 and a slant height of 12ft ,please help.
Answered by Penny Nom.
Two circles that touch each other externally 2014-04-08
From Ameya:
Two circles of radii a and b (a > b) touch each other externally. ST is a common tangent touching the circles at S and T respectively, then ST^2 is equal to
Answered by Chris Fisher.
The surface area of a rectangular prism 2014-04-08
From Manraj:
Find the surface area of a rectangular prism with dimensions 4, 5, and 7 units.
Answered by Penny Nom.
The sides of a triangle 2014-04-06
From Michael:
I am supposed to sove for the length of side "b" of an irregular triangle. I am given the following:
Side a: 65'
Side b: Find this length
Side c: 50'
Angle A: unknown
Angle B: unknown
Angle C: 52 degrees
I am supposed to use the law of cosines to solve for side "b" and my teacher says there is no mistake in the "givens" for the problem. I do not see how this can be done using the law of cosines and i have not figured out how to sove for angle B to use the law of cosines.

Answered by Penny Nom.
Cutting a hexagon from a disk 2014-04-05
From Paul:
I am a machinist and sometimes need to make a hex from round material.
If I know the distance of the flat sides opposite one another of my hex, how can I calculate the size of material I need to turn to give me the right diameter to finish the part with six sides?

Answered by Penny Nom.
A 4 digit number 2014-04-04
From LIM:
"A" is a 4 digit number formed by all the numbers from 1 to 4. When "A" is divided by 9, the remainder is the biggest possible value. What is the biggest value of A?
Answered by Chris Fisher.
The locus of a point 2014-04-04
From srishti:
A point P moves such that the difference between its distance from the origin and from the axis of x is always a constant c . what is the locus of the point?
Answered by Penny Nom.
3/4lbs of nails fills a container 2/3 full 2014-04-04
From Tyler:
If 3/4lbs of nails fills a container 2/3 full, then how many lbs of nails will fill the container?
Answered by Penny Nom.
Golf for 8 playing 7 rounds 2014-04-03
From Evan:
We are going on a golf trip to Scotland and are trying to work out the pairings. There are 8 of us playing 7 rounds. We would like to be partnered up in 2's with everyone once and have evenly split up foursomes. Thanks for the help
Answered by Victoria West.
Evaluate x-(3x+5) if x=-2 2014-04-03
From Destiny:
I wanted to know the value of x-(3x+5) if x=-2
Answered by Penny Nom.
Shadows of a father and son 2014-04-02
From esada:
the father and son cast a shadow of 11 feet and 8 feet,respectively if the son is 4'8'' in height,how tall is the father?
Answered by Penny Nom.
Is this a right triangle? 2014-04-01
From amina:
decide whether or not the following points are the vertices of right triangle (-9,2),(-1,-2),(-9,11)
Answered by Penny Nom.
A schedule for an 8 man golf team playing 4 each week 2014-04-01
From Harold:
We have an 8 man golf team and wish to schedule only 4 to play each week and to have each member play with one of the other 7 at least once. What is the simplest method. Number of weeks could be up to 18 or so.
Answered by Victoria West.
A cubical tank 2014-04-01
From renzo:
A cubical tank contains 2048 cubic ft of water when HALF-FULL. Find the total area of the tank and the length of its diagonal
Answered by Penny Nom.
Reducing the size of a poster by a scale factor of 1/3 2014-04-01
From deeshon:
eric is making a smaller copy of a poster that measures 20.4 cm wide by 34.2 cm long.he reduces the original by a scale factor of 1/3.what are the dimensions of the copy
Answered by Penny Nom.
The parameterisation of of a curve 2014-04-01
From Eunice:
Let C be the path along the curve given by y−80=−5x2 that moves from the point (5,−45) to the point (0,80). Find r(t) the parameterisation of C in that direction as t∈[0,5]. How am I suppose to find the parametric of both x and y?
can I let x=t, then y=-5t^2+80? thanks

Answered by Penny Nom.
An arithmetic progression 2014-03-31
From Japheth:
The 3rd term of an A.P is 10 more than the first term while the fifth term is 15 more than the second term. Find the first term?
Answered by Penny Nom.
9,-4,6,-8,3,... 2014-03-31
From Alynna:
You are given the following pattern: 9,-4,6,-8,3,...
Create a formula for the nth figure.

I have trouble finding the formula, I need help trying to find it.

Answered by Penny Nom.
A trig expression 2014-03-31
From Al:
the question is Find the value of sq rt 1-cos40/ 1+cos40( that is the square root of the numerator and denominator) I can't see what the question is about or even less an obvious answer Can anybody help?
Answered by Chris Fisher.
Golf with 20 players and one compulsory bye 2014-03-31
From Wayne:
I'm trying to run an event with 20 players, I would like if at all possible to limit amount of people playing repetitively together. (Mix it up and play with different people). Here's the conditions. I want groups of 4 over 5 rounds. On each round I want 4 players to drop out and have a bye (to help run the game) but I dont want them helping a group they've played in if I can help it. Is this possible ?
Answered by Victoria West.
The Pythagorean Theorem 2014-03-30
From brenae:
The Pythagorean Theorem, what is it?
Answered by Penny Nom.
A schedule for 6 people 2014-03-29
From John:
How do I set up a schedule where six people are here for ten of twenty days. Arranged in rotating groups of three, so everyone works with everyone else. Everyone works with everyone else at least once and everyone works ten days.
Answered by Victoria West.
Graphing piecewise functions 2014-03-29
From Rayven:
Hi! I'm in eighth grade, taking ninth grade algebra 1. I'm confused as to how to graph piecewise functions. I know that you have already answered a question similar to this (I did my research first) but it didn't completely help me on my homework. I have to graph piecewise functions for the specified domains, and create a table for the absolute values. I know that two bars around a number means absolute value (two bars around -2 makes it +2) , but how do I graph and chart the absolute value for the following:

f(x)= |x+3 | for -5≤x≤3

And then graph and chart: (on a separate graph):

f(x)= {x if x≤0
{x+1 if x <0

thank you!
~Rayven

Answered by Penny Nom.
A cyclic quadrilateral 2014-03-28
From Carly:
Suppose ABCD is a cyclic quadrilateral, i.e A, B, C, and D are the points on a circle, given in order going around the circle. Show that if we join each of A, B, C, and D to the orthocentre of the triangle formed by the other three, then the resulting line segments all intersect in a common midpoint.
Thank you.

Answered by Chris Fisher.
Curvature of the Earth 2014-03-28
From Max:

Recently I read the answer to a question proposed by someone on this site.

The question : What is the rate of curvature per mile on Earth?
The answer given : Use Pythagoras' Theorem to solve for the answer, given a 1 mile side
and a side as the radius. The hypotenuse minus the radius is your answer of drop/mile or curve/mile.

My conjecture : Why go through all of that work if the distance is one? Something like
{1/diameter} would would fine for such a problem. Seems like a lot of work for no reason.

I understand the practical application of Pythagoras' Theorem in this certain situation, as you would need
to use a^2+b^2=c^2 for any distance greater than one [mile]..
It just seems excessive and unnecessary if you're solving for curve / one mile.


Answered by Robert Dawson.
Percentage increase of the population of a town 2014-03-28
From hunter:
The population of a certain town in 1984 was 2900 people. The percent increase was 2.5% each year. What is the town's population in 2002?
Answered by Penny Nom.
12 golfers, 6 rounds 2014-03-27
From Bill:
I have a group of 12 golfers playing 6 rounds of golf. I am looking for a pairings schedule that allows each golfer to play at least one round in a foursome with each of the other eleven players.

Can you provide me with a solution?

Answered by Victoria West.
A table of values 2014-03-27
From Marisol:
A table value X 0,1,2,3,4,5,6 and Y 3,7,11,15,19,23,27 . what relationship of X to Y is represent by which equation? A . y= 4x. B y =x+3 . C y =4x+3 or . D y =4x-3
Answered by Penny Nom.
12 golfers, 24 weeks 2014-03-27
From George:
I have 12 golfers and want to set up a season schedule that will avoid duplication of playing partners as much as possible. The saeson is 24 weeks long. Do you have a formula?
Answered by Victoria West.
An inequality 2014-03-27
From James:
a step on a stairway is at least 8 inches high. write and solve an inequality to represent the maximum number of steps between floors that are 10 feet apart
Answered by Penny Nom.
13 golfers in groupings of 4, 3, 3 and 3 2014-03-26
From Lennart:
How can I organise 13 players playing in groupings of 4,3,3,3 for 3 rounds of golf in a way that all play with all others but a minimum of times with the same players(?)If possible, nobody should play in the 4 ball more than once. I would be grateful for an answer/proposal! Thank you, LR
Answered by Victoria West.
A word problem with fractions 2014-03-26
From lois:
a man has a stack of boards, he cuts 3/5 off each board, after he cuts the boards he finds he has enough pieces left to make 4 boards the length of the original boards. how many boards did he start with.
Answered by Penny Nom.
Justin and his father went fishing 2014-03-26
From Confused:
Justin and his father went fishing and together caught 12 fish. Three times the number of fish that Justin caught exceeds 12 by as much as 5 times the number that his father caught exceeds 8. How many fish did each catch?
Answered by Harley Weston.
The faces of a triangle 2014-03-24
From Westun:
Your answer says that a triangle has 0 faces but isn't the part of the shape you see the face!? Because i am having trouble with that so could you help me!
thanks! :)

Answered by Penny Nom.
9 golfers in groups of 3 2014-03-22
From Andrew:
We are a group of 9 golfers.
We play 4 rounds in 3 groups of 3.
What would be the most equitable where everyone plays with another at least 1 time...?. Thank you.

Answered by Victoria West.
Riding on a Ferris wheel 2014-03-21
From Claire:
A Ferris wheel has a radius of 72 feet and its center is 85 feet above the ground. At the top of the Ferris wheel, Sam is in the topmost car. If the Ferris wheel makes two complete revolutions per minute, how high above the ground will Sam be after 10 seconds?
Answered by Penny Nom.
An arithmetic sequence 2014-03-20
From Xabiso:
The 10th term of an arithmetic sequence is 28 and the 7th term is 19. Calculate the common difference and the first term of the sequence.
Answered by Penny Nom.
Three digit padlock combinations 2014-03-20
From Edwin:
Would appreciate if you can provide me with the list of different combinations that can be obtained from a three digits number. I lost the access code of a three digits number padlock (and need to open it order to get important documents
Answered by Penny Nom.
Ms. Werenich's nickels, dimes and quarters 2014-03-19
From London:
Ms. Werenich has twice as many dimes as nickels and 4 more quarters than nickels. If she has $4.50, how many of each coin does she have? What would the let statements be of this problem and can you solve it?
Answered by Penny Nom.
Find two numbers with a sum of -8 and a difference of 4 2014-03-19
From Elisabeth:
Find two numbers with a sum of -8 and a difference of 4. Let x be the greater number and y be the lesser number.
Answered by Penny Nom.
A formula for determining concrete volume in cu. yd. 2014-03-19
From Steven:
I know a couple of formulas for determining concrete volume in cu.yd. the one I use most frequently is length in feet x width in feet x thickness in inch. Divided by 324. It works every time. Where does the number 324 come from.
Answered by Penny Nom.
14 teams divided into two equal divisions 2014-03-18
From C:
We have 14 teams divided into two equal divisions. We want each team to play each team in their division one time and four teams from the other division one time. What is the schedule
Answered by Victoria West.
Markup 2014-03-17
From Lorriane:
I work for a plumbing company and our new financial manager said we should mark up all parts we buy by 142.86 to get a 30% mark up, however if we buy something for $100.00 we charge $130.00 being 30%. If we use the other method the customers will be paying $142.86 for $100.00 and they still say that this is only 30% mark up. We have for years been taught percentages at school and also the Government charges us 15% GST which on $100.00 would be $15.00 so who is correct. Thank you for your wonderful website Lorriane
Answered by Chris Fisher and Penny Nom.
A circle inscribed in a right triangle 2014-03-16
From akshaya:
A circle with centre O and radius r is inscribed in a right angled triangle ABC. If AB=5 cm, BC=12 cm and < B=90*, then find the value of r.
Answered by Penny Nom.
2 rectangular prisms are similar by a scale of 0.75 2014-03-16
From gina:
2 rectangular prisms are similar by a scale of 0.75. The volume of the smaller prism is 27cm3 (cubed). How many cubic centimeters is the volume of the larger prism?
Answered by Penny Nom.
Two overlapping arcs in a square 2014-03-15
From Jean:
I have a square with side 4 cm. There are two overlapping arcs going from vertex to diagonal vertex. The other two vertices are the center of the arcs, which are shaded. How do I find the area of the shaded arcs? The overlapping arcs when shaded resemble a long thin football
Thank you for your help.

Answered by Penny Nom and Walter Whiteley.
The area of a 5 sided lot 2014-03-15
From Michael:
Question from michael:

This lot is in feet. 59x154x109x188x137 per the plot plan

Answered by Harley Weston.
40 meters increased by 20% 2014-03-14
From Kyle:
I need help finding out this question: 40 meters increased by 20% Is the answer 800 or is it 8?
Answered by Penny Nom.
Three consecutive whole numbers 2014-03-13
From Abhishek:
Three consecutive whole numbers are such that if they be divided by 5,3 and 4 respectively, the sum of the quotient is 40. What are the numbers?
Answered by Chris Fisher.
A chord length of 2 cm 2014-03-13
From prema:
I am having only chord length as 2cm. how to find arc length and degree
Answered by Penny Nom.
A cable around the Earth 2014-03-13
From fikile:
By how much must an equatorial cable be extended in order that it runs 1meter above the ground?
Answered by Penny Nom.
A parabolic suspension bridge 2014-03-11
From jeffrey:
the towers of a parabolic suspension bridges 200 meter long are 40 meter high and the lowest point of the cable is 10 meter above the roadway.Find the vertical distance from the roadway to the cable at 50 meter from the center.
Answered by Penny Nom.
8 golfers for 7 rounds 2014-03-11
From Brian:
We have 8 guys playing 7 rounds of golf. We want to play with each player as a partner only once, sounds simple but i can not come up with the match ups beyond the first 4 matches. I believe the numbers should work perfectly where each player can play with another as a partner only once each throughout the week. Please help.
Answered by Robert Dawson.
The ratio of boys to girls is 5:3 2014-03-10
From jane:
The ratio of the number of boys to the number of girls in the concert hall is 5:3. After additional 28 boys entered the concert hall, the ratio of the number of boys to the number of girls become 3:1 How many girls are their in the concert hall?
Answered by Penny Nom.
24 golfers playing 3 rounds 2014-03-10
From Jim:
How can I rotate 24 golfers playing 3 rounds of golf so that none of them play with the same person twice.
Answered by Victoria West.
A circle which is tangent to two perpendicular lines 2014-03-09
From MJ:
I'm a College Student taking up Bachelor of Secondary Education on Math Subject. And I'm struggling for my research about Circles. I done solving the said topic particularly on this question:

"What are the possible equations of a circle being tangent to a pair of perpendicular lines, having the origin as the Point of Intersection and the C (h, k), where h, k ∈ℤ"

But I can't get what would be the process that I must do in order to jive to my idea/goal for that problem.
Please check my idea that the numerical coefficients of the equation is equal to the radius of the circle. Thanks in advance! :)

Answered by Penny Nom.
The greatest common divider of n^2-3n-1 and 3 2014-03-09
From Rimoshika:
determine the greatest common divider (n^2-3n-1,3)
Answered by Penny Nom.
A word problem 2014-03-09
From Joanne:
Ashley weighs 5kgs more than Joyce. Their total weight is 41 kgs. What is the weight of Ashley?
Answered by Penny Nom.
A schedule for 6 teams over 12 weeks 2014-03-09
From Paul:
So I have a question. I noticed you came up with ways to create schedules and we are having a really hard time making our lineup correctly. Basically we have 6 teams that will play over a 12 week period every Monday night. The time slots are 1 hr each playing at 6, 7 and 8. We would like each team to play 3 games at each time slot over the 12 weeks. Is this something that can actually be accomplished?
Thanks so much for your help!

Answered by Eric Venables.
Eleven golfers 2014-03-08
From Leon:
I have a group of 11 golfers wanting to play 10 rounds of golf in grouping of 4,4,3 .What is the best solution so that everyone plays each other as many times as possible
Answered by Victoria West.
Simple interest 2014-03-08
From lynn:
I need to find what the interest will be for: 5000.00 @ 16.5% annual rate, and the same for 10.8 % for 5000.00 annual rate all one question

thank you for your aid

Answered by Penny Nom.
The volume of scale in a pipe 2014-03-08
From Sid:
What is the estimated volume of scale (Liters) if you have a 12 inch ID pipe,300 feet long with scale 1/2 inch thick. Please show me the method and formula. Thank you for your assistance.
Answered by Penny Nom.
The angle of depression 2014-03-08
From Ranger_minor:
A woman of height 1.4 metres standing on the top of a building 34.6 metres high views a tree some distance away. she observes that the angle of depression of the bottom of the tree is 35 degrees and the angle of depression of the top of the tree is 29 degrees.

assume that the building and the tree are on level ground :
1). calculate the distance of the woman from the top of the tree measured along her line of sight.

Answered by Penny Nom.
Determine the selling price 2014-03-08
From augustine:
knowing an auctioneer charges a 7% fee and I know I want $74,400 what is the formula to determine selling price.
Answered by Penny Nom.
The equation of a circle 2014-03-07
From Balraj:
I have to draw a circle x^2+y^2 =8x . please tell me how to understand these coordinates ? please elaborate , on how to understand these types of equations.
Answered by Penny Nom.
What are the possible lengths of the hypotenuse? 2014-03-07
From audrey:
The three sides of a right angles triangle measure x-2, x+5, and 2x-1 in length. What are the possible lengths of the hypotenuse?

... I'm doing the equation c2=a2+b2 and subbing in the numbers but nothing makes sense

Answered by Penny Nom.
Mixing oil and gas 2014-03-07
From Geoff:
What amount of oil would I need to mix on 50-1 basis for a-4litre tank (13.57ozs) capacity tank. Thank you
Answered by Penny Nom.
29% as a fraction 2014-03-07
From kylie:
29% into a fraction or mixed number
Answered by Penny Nom.
The inverse of y = 5^x 2014-03-07
From Melody:
how do you find the inverse of y = 5^x
Answered by Penny Nom.
Parallel chords 2014-03-06
From Raj:
AB andCD are two chords which are in the same side of the circle.The length of AB=12 and CD= 24.if the distance between them is 4 then find their radius. Pls help me I just believe on you guys I am having my exam after 3 days
Answered by p.
A circle graph 2014-03-06
From Caitlyn:
I need to find the measure of the central angle that represents the amount of time spent on each activity.
My question includes a circle graph with the following: Sleep 31%, Other 15%, Entertainment 18%, Errands 7%, Work 20%, and Food 9%.

Answered by Penny Nom.
A cone inscribed in a sphere 2014-02-28
From joel:
how can I find the radius and the height of a cone INSCRIBED in a sphere, given the sphere having a radius of 6? ( note: the diameter of the cone is equal to its slanted height).
Answered by Penny Nom.
Four digit phone numbers 2014-02-25
From Tom:
Hi, I'm an online math teacher, working on lessons for my students.

This question is in their book and I can't do it...! Help!

It has to do with phone numbers, and in this problem, we are only dealing with the last 4 digits of the number.

It asks how many possible numbers we have if at least one digit repeats in the last 4 digits of the number.

Answered by Penny Nom.
A speed word problem 2014-02-24
From kiss:
Hank bicycles 5 km/h slower than Kelly. In the time that it takes Hank to bicycle 42 km, Kelly can bicycle 57 km. How fast does each bicyclist travel?
Answered by Penny Nom.
A word problem 2014-02-23
From Anh:
The Texas State Legislature is comprised of state senators and state representatives. The sum of the number of senators and representatives is 181. There are 119 more representatives than senators. How many senators and how many representatives make up the Texas Legislature?
Answered by Penny Nom.
The diameter of the base of a cone 2014-02-23
From elwin:
i have a sector of a circle that has 120 degree and 6 cm length. What will be the diameter of the base of the cone.
and what is the diameter of the angle is changed to 180.

Answered by Harley Weston.
A word problem with fractions 2014-02-23
From alex:
In a certain fraction the number by n the denominator is greater than the number by3.If 2 is added to both the numerator and denominator ,the fraction is increased by 6/35..Find the fraction.
Answered by Penny Nom.
x^3+(1/x^3)=18√3 2014-02-23
From Asiv:
if x^3+(1/x^3)=18√3; then what is the value of x?
Answered by Penny Nom.
Paycheck after deductions 2014-02-23
From Louise:
So I got a paycheck for 89.02 they took out in deductions 15.69. I want to know the percentage they are taking out so that I can figure my take home pay each week before I get it. So I know what to expect for pay each week so I can budget my bills from now on a weekly basis. If I know the percentage than I can just figure out the percentage through how many hours in the week I worked and multiply my gross pay and know what my take home will be
Answered by Penny Nom.
Some 3-digit combinations 2014-02-23
From ivana:
How many possible 3-digit combinations can be made of the numbers 123456? None of the numbers can repeat in one combination. I used to know a formula but have been out of school for some time and cannot remember.
Answered by Penny Nom.
9 golfers divided into 3 teams 2014-02-22
From Steve:
We have 9 golfers, divided into 3 teams each day. Play is over 6 days. Can you devise a schedule to ensure pairings allow for all golfers to play at least once with all participants? Also, that the pairings have one player from another team.
Answered by Victoria West.
Three investment partners sharing the profit 2014-02-22
From Ayatullah:
Hello;

We are three partners and bought a property at 2050000 and sold at 2300000.
Details of investment of the partners
X= 1500000
Y= 400000
Z = 150000

My questions are
1) How could i calculate percentage of investment of each partner?
2) How could i deduct 30% commission from each partner in profit?
3) How could i distribute the profit amongst the partners?


Thanks in advance

Answered by Penny Nom.
A circle through three points 2014-02-22
From Mohammad:
Find the equation of circle passing through the origin and the points (a,b) and (b,a). Find the length of chords that it cuts off from the axes.
Answered by Chris Fisher.
Finding the retail price 2014-02-22
From Judy:
An item is currently on sale at 37% off the retail price. The item now sells for $350.

My Question:

What is the retail price and what is the formula or steps to figuring that out?

Answered by Penny Nom.
A limit with trig functions 2014-02-22
From pearl:
(what is the value of limit of x as it approaches 0 of sin8x divided by cos6x)
Answered by Penny Nom.
8 team schedule over 7 days 2014-02-21
From Andrea:
I need to organize 8 teams. Each team has to go through 8 games against another team, but not against the same as before.
Answered by Victoria West.
2.3% of $17.3 trillion 2014-02-21
From C:
What is the annual interest on $17.3 trillion at a rate of 2.3%. Thank you
Answered by Penny Nom.
Gradient 2014-02-21
From Nancy:
calculate the gradient of the line AB when the line AB is passing through the points A (2,1,) and B ( 4, -3).)
Answered by Penny Nom.
A 7 person golf schedule 2014-02-21
From Claude:
Golf Holiday: 7 guys, play a 4-some and a 3-some each day for 10 days. Want to have the best balance of each player playing with every other player the same number of times and each player playing in an equal number of 4-somes and 3-somes.
Answered by Victoria West.
The length of my property 2014-02-19
From James:
I have 4.3 acres. My property is 650 feet wide. What is the other length?
Answered by Harley Weston.
A fountain surrounded by a walk 2014-02-18
From Maddie:
A square Water Fountain is Surrounded by a walk 2 yards wide. If the Area of the Fountain is 2/3 of the total area of the Fountain and the Walk. What are the Outside Dimensions of the Walk
Answered by Penny Nom.
The graph of y=2x+4 2014-02-18
From tyler:
y=2x+4 graph
Answered by Penny Nom.
Paul is making banana bread 2014-02-17
From John:
Paul is making banana bread. The number of cups of bananas he uses is proportional to the number of loaves of bread. Paul uses 11 1/4 cups of bananas to make 5 loaves of bread. Which equation represents the relationship between c, the number of cups of bananas, and b, the number of loaves of bread?
A) C=4/9 b
B) C=2b
C) C= 2 1/4 b
D) C=5b

Answered by Penny Nom.
Selecting a card 2014-02-16
From Akarsh:
Cards numbered 1 to 1000 were put in a box.Ali selects cards at random.What is the probability that Ali selects a card containing at least one'3'?
Answered by Penny Nom.
The growth of a tree 2014-02-16
From Emily:
If a tree is 10 ft tall after 2 years and 25 ft tall after 5 yrs , find the rate of change of growth Of the tree if y is the height in ft and x is the number of years.
Answered by Penny Nom.
What is the exponential form of 1/square root of 6v? 2014-02-16
From Prince:
What is the exponential form of 1/square root of 6v
Answered by Penny Nom.
Simultaneous fractional equations 2014-02-15
From benjamin:
hi math central. benjamin here. during class, i had problem with this topic. normally i wont have problems with math but this topic i just too hard for me. please help i am having exam and test next week on this topic

here is the question:
using substitution method, solve the simultaneous equation.
(x+1)/(y+2)=0.5

(x-2)/(y-1)=1/3

Answered by Penny Nom.
The grade of a road as a percent 2014-02-14
From Emily:
What is the grade of the road shown below expressed as a percent rounded to one decimal place?
Rise is 40feet
Run is 380 feet

Answered by Penny Nom.
Rolls of window film 2014-02-14
From Travis:
This question is probably close to the same question as "roll of paper"

We have Rolls of Window Film that we are trying to figure out an equation for a spreadsheet that we can use to "inventory" our window film.

We use a caliper tool to measure the thickness of the roll in millimeters.

the core thickness = 1.90mm
Full Roll thickness(including core) = 9.08mm to 9.12mm
Film thickness = 0.06

Full Roll of Film is supposed to average 1200" of film

What equation could we use to get the approximate inches left remaining on the roll if we measured the roll including the core with the Caliper tool in Millimeters?

Answered by Harley Weston.
Some mixed nuts 2014-02-12
From Andrew:
How many kg of mixed nuts that contain 30% peanuts must Paul add to 6kg of mixed nuts that contain 38% peanuts to make a mixture that contains 33% peanuts?
Answered by Penny Nom.
A word problem 2014-02-11
From cyril:
In a rectangle,the length is 1.5 times the breadth.if the length is shortened by 3 m and the breadth is lengthened by 3 m, the rectangle will be a square. Calculate the dimensions of the rectangle.
Answered by Penny Nom.
Water in a conical funnel 2014-02-11
From Marcus:
Water is running out of a conical funnel at the rate of 1 inch^3/sec. If the radius of the base of the funnel is 4 in. and the altitude is 8 in., find the rate at which the water level is dropping when it is 2 in. from the top.
Answered by Penny Nom.
How many cubic centimeters are in a cubic meter? 2014-02-11
From merylin:
How many cubic centimeters are in a cubic meter? Use a sketch to explain your reasoning.
Answered by Penny Nom.
A sequence 2014-02-10
From Joshua:
hello..the question I have today is... A sequence... 1,5,14,30,55,91 find the general terms.
Answered by Penny Nom.
A square garden 2014-02-09
From reeta:
Inside a square garden of side 158m, a road 4m wide is built all around. What is the area of the remaining part of the
Answered by Penny Nom.
A ball in a box 2014-02-09
From kenneth:
I have 2 questions.What is the radius of the largest ball that will fit into a box that has the inside dimensions of 6feet by 8 feet by 10feet. and the second question is how many cubic feet of concrete will you need to complete a patio that is 20 feet long by 15 feet wide by 5 inches in hight.
Answered by Penny Nom.
8 golfers, 11 rounds 2014-02-09
From Clare:
I am leading a group of 8 golfers who will be playing 11 rounds each at the end of next month and have been tasked with coming up with a schedule that allows, as close as possible, that has everyone playing an equal number of rounds with each other. Do you have any suggestions?
Answered by Penny Nom.
The volume of a cone 2014-02-08
From hibba:
why is the volume of right circular cone divided by 3?
Answered by Penny Nom.
Can a cylinder be considered a circular prism? 2014-02-08
From Davina:
Can a cylinder be considered a circular prism?
Answered by Penny Nom.
The graph of f(x)=x^2-4 2014-02-07
From Allison:
Graph f(x)=x^2-4 and give the five point of the x/y intercepts.
Answered by Penny Nom.
Pizza for 24 2014-02-07
From Delaney:
if 8 people eat 2/3 of a honey chicken pizza how many pizzas are need to feed 24?

How is this problem solved. Thank you!

Answered by Penny Nom.
A number with all the digits different 2014-02-07
From Jon:
I'm not a mathematician but just curious. Is there a name for a number of up to ten digits where each digit is different, i.e the equivalent of an isogram in linguistics? My online banking gives me a random 8-digit number each time I log on and it is rare to get one of the type I refer to. There must be calculable odds, but I'm only allowed one question!
Thanks in advance
Jon

Answered by Harley Weston.
Two bicyclists traveled in opposite directions 2014-02-07
From Susan:
Two bicyclists traveled in opposite directions, one at a rate of 8 km/hour and the other at a rate of 7 km per hour. In how many hours were they 45 km apart?
Answered by Penny Nom.
Prime factorization 2014-02-06
From Kadeejah:
Write the prime factorization of 37 in exponential form
Answered by Penny Nom.
Walking up and down a hill 2014-02-06
From flo:
michelle walks 4 km to the top of a hill at 3 km/h then immediately walks back down at an average speed of 5 km/h what is her average speed for the 8km walk
Answered by Penny Nom.
A triangle has angels in the extended ratio of 2:5:8 2014-02-06
From Rubina:
a triangle has angels in the extended ratio of 2:5:8. find the measure of all three angles?
Answered by Penny Nom.
Converting cost per cubic yard to cost per ton 2014-02-05
From Mayra:
If 18 cubic yards= 25 tons and it's $28.00 per yard how much is it a ton. I need help please a refresher on my algebra. Thank you
Answered by Penny Nom.
Order of operations 2014-02-04
From Alex:
Hi there,i got problem with order of operation.Can you please help to find a solution for this?
Thank u beforehand
6-3(7+2)+(2+4)/3-4.

Answered by Penny Nom.
A square and a triangle 2014-02-02
From Veronica:
The perimeter of a square piece of land is twice the perimeter of an equilateral triangukar lot, if one side of the square is 60 meters, find the length of a side of the triangle.
Answered by Penny Nom.
The volume of a frustum 2014-02-02
From mike:
volume of frustum R23", r 18", h 16"
Answered by Penny Nom.
Conics 2014-02-01
From Kassidy:
Hey, I have searched through all the questions about conics and how people use them in the real world, but none of them were very specific on how they are applied and the process, why it's so important etc. I have a project due asking these questions and it's been very difficult finding the right answer, if you could name jobs, how they are use and specifically applied that would be greatly appreciated.
Answered by Penny Nom.
The dimensions of a room 2014-02-01
From jenna:
The length of a rectangular room is 2m more than the width. Find the dimensions if the perimeter of the room is 34m
Answered by Penny Nom.
Adding fractions 2014-01-31
From bianco:
2/3+3/4=
9/8-6/8=

Answered by Penny Nom.
Related rates 2014-01-30
From Veronica:
A container is the shape of an inverted right circular cone has a radius of 1.00 inches at the top and a height of 5.00 inches. At the instant when the water in the container is 1.00 inches deep, the surface level is falling at the rate of -2.00 inches/second. Find the rate at which the water is being drained.
Answered by Penny Nom.
A sequence 2014-01-30
From joshua:
hi...really struggle with one question that the teacher gave us...
The sequence is 1,2,1,5,8,1,11,___,___

Answered by Penny Nom.
A man and a kite 2014-01-29
From Veronica:
A man flies a kite at a height of 120 meters. The wind carries the kite horizontally away from him at a rate of 8 meters/second. How fast is the distance between the man and the kite changing when the kite is 130 meters away from him?
Answered by Penny Nom.
A bizarre percentage problem 2014-01-29
From matthew:
by what percent was the child's sodium level beneath the normal range? the child's sodium level was 107 where the normal is 136-145
Answered by Harley Weston.