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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.
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.
People on a bus 2013-11-28
From jeric:
3/10 of the passenger in a bus were men, 2/7 of the remainder were women and the rest were children, if there were 50 passengers in the bus, how many more children than women were there?
Answered by Penny Nom.
Three roommates share the rent 2013-11-23
From Cortlin:
Because of different bedroom sizes, three roommates decide to split the rent this way: Roommate A pays 75% as much as B does, and C pays 40% as much as B does. What fractional part and percent of the rent does each roommate pay?
Answered by Penny Nom.
Linear equations 2011-10-06
From Hannah:
I am confused about a question on my homework, here is an example on what I need to do:

You own a sightseeing boat tour. Kids' admission costs $5, adults' admission costs $8. During that day you get (made-up number) $521 with 71 admissions. How many of each passenger boarded?

I tried something like
5x + 8y = 521
x + y = 71

But, I still don't understand how to solve it! Help?

Answered by Penny Nom.
Deciding where to bowl 2011-04-29
From ella:
the bowling alley on wedge street charges $5.50 for shoe rentals plus $2.50 per game. lawerence bowing alley charges $4.00 shoe rentals and $3.00 per game . how many games should they bowl to make wedge street cheaper than lawerence street
Answered by Penny Nom.
Fifty votes were cast in a class election 2010-12-03
From nympha:
Fifty votes were cast in class election, Beth got 1/5 of the votes. Helen got as many votes as Jane and Peter put it together. Peter got 1/3 as much votes as Jane. How much votes did each of the four candidates received?
Answered by Stephen La Rocque.
A box full of oranges 2010-10-28
From Mary:
A box full of oranges weighs 9 pounds. After a family ate 2/3 of the oranges, the remaining oranges and the box weighed 4 pounds. The weight of the box when empty is how many pounds?
Answered by Penny Nom.
Working backwards 2010-04-11
From adel:
alice gave reggie and freddie as much money as each had already.reggie in turn gave alice and friddie as much money as each already had in negotiable treasury notes. freddie gave alice and reggie as much money as they each had. in the end they each had the same sum, 24000.00.how much money did they each in the beginning?
Answered by Penny Nom.
15 men can do a piece of work in 7 days 2010-02-20
From Kenneth:
If 63 books cost $126, what will 125 books cost?

If 15 men can do a piece of work in 7 days, in how many days can 21 men do the same work?

Answered by Penny Nom.
Setting up an algebraic equation 2010-01-18
From jerry:
the 1st of 4 books has twice as many pages as the 3rd. The 2nd book has 30 pages less than the 1st. The 4th has 42 pages more than the 1st and 2nd books combined. there are 567 pages in total. How many pages are in each book.
Answered by Penny Nom.
Jogging and swimming 2009-09-11
From Brandon:
Trevor swims jogs 3 days and swims every 4 days. How often does he jog and swim on the same day
Answered by Leeanne Boehm.
Two word problems 2009-07-31
From Lee:
1) a student saved $50.25 in one month. at that rate how long will it take the student to save $700?

2) for summer job, martin shampooed rugs. he could finish a 4mx 4m rug in 30 min. his supervisor could finish a similar:smaller rug in 20 min. how long would it take for them to finish the rug if they worked together?

Answered by Robert Dawson.
The girl guides bake sale 2009-07-20
From Barbra:
here is two questions i need help with,
1.)A toastmasters tea was attended by 550 people. Students paid 75 cents for their tickets, and the adults paid $1.20. if the recipts totaled $525, how many adults and how many students attended?
2.) One cookie and six bars cost $2.00 at the girl guides bake sale. At the same sale, three bars and six cookies cost $2.10. Find the cost of one cookie and the cost of one bar.

Answered by Penny Nom.
The height of a mountain peak 2009-03-23
From james:
Can you please help us (my son Jim geometry) out with this problem, we cannot seem to find the correct method of solving, not sure how to solve the scalene triangle with what is given...if that's the correct method?? Can you please explain how this is solved!!

Thank you so much,

Jim and son !

Answered by Harley Weston.
The angles in a parallelogram 2009-03-03
From dolly:
having a time-with equations inequaltites and problem solving= the sum of the measure of the angles of a parallelogram is 360.anglesa a and d , have the same measure as angle c and d,c is twice the measure of angle a, what is the angle for each.
Answered by Penny Nom.
Randy' age and Mandy's age 2009-02-03
From carolina:
Randy is 4 times as old as Mandy, in 12 years, Mandies age is half of Randy's . how old is each now?
Answered by Penny Nom.
Two methods of payment 2009-01-13
From adjoa:
owen was offered $225.00per week plus 3%on sales, or 15%of sales with no salary. How much must he sell before the second method of payment gives him the highest pay? Express your answer to the nearest dollar.
Answered by Penny Nom.
Who am I? 2009-01-09
From daphne:
im a 2-digit number less than 85.the sum of my digits is 9.the number in my ones place is twice my tens digit. who am i?
Answered by Robert Dawson and Harley Weston.
What day of the week will it be? 2009-01-09
From dan:
suppose 3 days ago was a wednesday. what day of the week will 365 days from today be?
Answered by Robert Dawson.
Brothers and sisters 2009-01-09
From Jade:
Pat, Joe, Dave,Yoly, Dolor and Alma are three brothers - and sister - pairs who play double tennis. Brother and sister ca not play in the same pair. Pat and Yoly play Dave and Dolor on one day. Dave and Yoly play Joe and Alma on another day. Name each brother - and sister pair, in any order.
Answered by Robert Dawson.
Quadratic equations arising from practical problems 2008-11-24
From Lenval:
Why do quadratic equations arising from practical problems often give physically impossible solutions such as negative distances, negative times or, say, a polygon with a negative number of sides? For example: "A river in flood carries a tree t-squared - 23t metres downstream in t seconds. How long does it take for the tree to be carried 50 metres downstream?" This gives t=25 and t=-2. Please explain the second 'solution', which is not physically possible.
Answered by Chris Fisher and Victoria West.
Two problems involving reciprocals 2008-08-10
From Dee:
I have a few questions that im have trouble working out...

1. One number is three times another number; if each is increased by 1 the sum of the reciprocals is 10/21. Find the numbers

2.A tank can be filled by 2 pipes together in 6 hours; if the larger pipe alone takes 5 hours less than the smaller to fill the tank, find the time in which each pipe alone would fill the tank

Answered by Penny Nom.
Three workers working together 2007-12-18
From Rajesh:
Worker A can do a piece of work in 15 days, worker B in 12 days, and worker C in 10 days. Worker A works 2 days, worker B 3 days, and worker C 3 days. In what time can worker A and worker B finish the job by working together?
Answered by Penny Nom.
Problems solved using quadratic equations 2007-10-07
From Lisa:
a. Two positive numbers differ by 5. Their product is 234. What are the two numbers? b. The sum of two numbers is 12. Their product is 30. What are the two numbers? c.Two numbers differ by 5. Their squares differ by 55. What are the two numbers? d. The sum of two numbers is 15. Their product is 56. By forming an equation, find the two numbers.
Answered by Penny Nom.
Word problems 2007-04-13
From Perla:
1.A school district is proposing a 5% increase in the numbber of days in a school year. How long would a school year be with the proposed increase?

2. Keikio spent the day bird watching and counted 34 more birds in the morning than in the afternoon. If she counted a total of 76 birds, how many birds did she count in the afternoon?

Answered by Penny Nom.
Word problems 2007-04-09
From Danielle:
I am teaching a student who cannot understand which operation to use when doing word problems. I have tried a number of different ways to show him...any suggestions?
Answered by Haley Ess.
Alligation 2007-02-09
From Shanah:
Orders: 360 mL of 75% acetic acid Stock: 99% acetic acid and distilled water Find the volume of acetic acid and distilled water to get the needed concentration. Any help with this is greatly appreciated, Thanks
Answered by Stephen La Rocque.
Two word problems 2006-10-02
From Eve:

1. A surveyor's map shows a plan for the rectangular rose garden whose area is
a2+25ab-350b2. Find an algebraic expression for the length and width. If a=20 ft and b=10 feet, find the actual dimensions of the garden.

2.A square is enclosed in a circle. The area of the square is (4r2-32r+64)sq cm and the area of the circle is 484r2 sq cm. Write a polynomial in factored form to represent the difference of the two areas.

Answered by Stephen La Rocque.
Three questions 2006-05-17
From Diane:



What is the largest real number less than 10?
1- there is no largest real number less than 10 or
2- 9
3- 9.999...


Given that not (a and b) implies c.What does
(not c) imply ?
1-a and b
2- (not a and b) or (a and not b)
3- (not a and b) or (a and not b)
4- a or b


What are the x and y intercepts of the equation
2x + 3y -6 =0 ?
1- x=3 and y=2
2- x=6 and y=-2
3- -3x + 2y =0

Answered by Paul Betts.
A word problem with fractions 2006-05-02
From Stuart:
I have 54 1/4 yards of material. i need to cut as many pieces as possible out of it that are 3 1/12 long. how many pieces will you get and how much is left over?
Answered by Stephen La Rocque.
The box of maximum volume 2006-02-01
From Elizabeth:
A box factory has a large stack of unused rectangular cardboard sheets with the dimensions of 26 cm length and 20 cm width.
The question was to figure what size squares to remove from each corner to create the box with the largest volume.
I began by using a piece of graph paper and taking squares out. I knew that the formula L X W X H would give me volume. After trial and error of trying different sizes I found that a 4cm X 4cm square was the largest amount you can take out to get the largest volume. My question for you is two parts

First: Why does L X H X W work? And second, is their a formula that one could use, knowing the length and width of a piece of any material to find out what the largest possible volume it can hold is without just trying a bunch of different numbers until you get it. If there is, can you explain how and why it works.

Answered by Penny Nom.
Word problems 2006-01-27
From Duk:
One kind of candy sells for 90cents more a pound than another kind. A pound of each sells for a total of $5.10. What is the selling price of each kind?

A soft drink sells for 20 cents more than the deposit required on the bottle. The cost of the soft drink and the bottle deposit totals 70cents. How much is the soft drink? The bottle deposit?

Answered by Penny Nom.
Two word problems 2005-11-14
From Jennifer:

1. Every other person on a school's parent advisory committee is surveyed to determine how many people support passage of a school bond to build a new elementary school. Is this a good sample? Why or why not?

2.What is the difference in elevation between the highest point in California,Mount Whitney,which towers 4421 meters above sea level, the lowest point in California,Death Valley, which lies 86 meters below sea level?

Answered by Harley Weston.
Mario is 16 years older than his youngest sister, Mercedes. 2005-11-08
From Jennifer:
Mario is 16 years older than his youngest sister, Mercedes. Together, their ages total 36 years . How old is each person?
Answered by Paenny Nom.
Jim is travelling from Toronto to Ottawa 2005-08-15
From Eleanor:
Hi! I am looking for an easy way to solve this type of question: Jim is travelling from Toronto to Ottawa, a distance of 435 miles. He travels part of the way at a speed of 100 km/h and because of an accident, he uses a secondary road and travels at 70 km/h. If the trip took him 6.5 hours, how far did he travel on each of the two roads.
Answered by Penny Nom.
Three word problems 2004-09-12
From Adrian:

1. Increasing area of a field: Julia's soybean field is 3m longer than it is wide. To increase her production, she plans to increase her to increase both the length and width by 2m. If the new field is 46m2(2nd power) larger than the old field, then what are the dimensions of the old field?

2. Width of a Football Field: If the perimeter of a football field in the NFL including the end zones is 1040 ft and the field is 120 yd long, then what is the width of the field in feet?

3. Fencing dog pens Clint is constructing two adjacent rectangular dog pens. Each pen will be three times as long as it is wide, and the pens will share a common long side. If Clint has 65 ft of fencing, what are the dimensions of each pen?

Answered by Penny Nom.
Quadratic word problems 2003-03-30
From A student:
i think i know the basics of how to solve direct quadratic equations,but how do i go about solving those word problems? i have tried them times and again, but nothing seems to work at all!they are driving me crazy! pls help!:):):):):)

  1. bob & nick earned $1260 each. bob's hourly wage is $3 more than nick's hourly wage. he worked 2h less compared to nick. find the number of hours nick worked.
  2. there are 2 tanks in henry's house. in tank A, the fish are all goldfish. they are bought at a total cost of $259. in tank B, there are only guppies. the guppies were bought at a cost of $1.20 each. a day later,henry bought 3 more goldfish and put them into tank A. the number of guppies in tank B is now twice the number of goldfish in tank A.the total cost of all the fish that henry has presently,i.e. goldfish & guppies, is $355.30. given that the cost of each goldfish is the same,
    a)find the initial number of goldfish in tank A
    b)find the total cost of all the guppies.
  3. a particular disc can be made to rotate at 2 different speeds. if it is made to rotate slower by 135 revolutions per hour, it wld require an additional 2.7 hour to make 315 revolutions. find the higher speed at which it can operate.

Answered by Penny Nom.
Problem solving 2003-02-03
From Brigitte:
My daughter is having lot's of problem with problem solving she is in grade 6. she is using mathematics in action from macmillan/ mcgraw- hill. Do you know of any way she can get help, and if there is any tests on line
Answered by Diane Hanson.
Some 5th grade problems 2003-01-24
From Sabrina:

[What is the greatest common factor of 20,28, and 36?] next problem is

[5k+7(k+8)= ] next problem

[Curtis simplified 0.8 divided by 0.2 x 0.04 and got 10. Latoya Simplified and got 1.6. is either correct? Can you explaine how you got the answer please.]

Answered by Penny Nom.
Two problems 2002-10-14
From Seçkin:
i am from turkey i am a teacher in a collage i have two difficult question which i havent solve yet these are very important for me....
Answered by Claude Tardif.
$100 is split between four guys. 2002-10-03
From Stephan:
$100 is split between four guys. A,B, C, and D. How much money does if person get if B has four more dollars than A, C has 8 more dollars than B, and D has twice as much money as C?
Answered by Penny Nom.
Three problems 2001-10-28
From Brenda:
  1. Joseph is planting bushes around the perimeter of his lawn. If the bushes must be planted 4 feet apart and Joseph's lawn is 64 feet wide and 124 feet long, how many bushes will Joseph need to purchase?

  2. The cost of a long distance phone call is $1.50 for the first two minutes and $0.60 for each additional minute. How much will Maria pay for a 24 minute phone call?

  3. Find the next three numbers in the pattern. 1,3,7,15,31,___,____,___.

Answered by Penny Nom.
What did the girls score on average? 2001-07-20
From Rajesh:
The students of two schools were sitting the same test. The students attending the first school scored 74 on average; within this the average scores of the boys and the girls were 71 and 76, respectively. The corresponding scores in the other school were 84, 81 and 90, respectively. If the average score of all boys was 79, what did the girls score on average?
Answered by Penny Nom.
Geometry problems involving triangles 2001-06-07
From Sandi:
Find the radius of the largest circle contained in a right triangle whose legs are 8 and 15 and hypotenuse is 17. If the right triangle has legs a and b and hypotenuse c, find an expression for the radius of the circle.
Answered by Penny Nom.
A few problems 2001-04-22
From Carol:
Hello I am a College student trying get through my elmentry concepts class. I am also working with the middle and elementry school student with their work. I was given a few problems to work on and i am having a hard time explaining them to students. DO you think you can help with a coupld of these questions!
Answered by Penny Nom.
Parabola problems 2001-04-10
From Kathleen:
  1. Graph each function and state its domain and range. y = 3x2 + 4

  2. For each parabola find: i) the direction of opening
    ii) the coordinates of the vertex
    iii) the y-intercept
    iv) the x-intercepts
    y = x2 + 3

  3. Find the equation of each parabola vertex at (0, -2) and passing through the point (3,7)

Answered by Harley Weston.
12 RTV's 2001-03-27
From Christine:
  1. In order to promote the 2000 Census and encourage participation, 12 Road Tour Vehicles(RTV's) set out from 12 locations across the US for a 10 week promotion tour last February. The RTV's reportedly traveled a total combined distance of 97,911 miles. What was the aberage number of miles traveled in a day by each RTV?

  2. 2. The 12 RTV's mentioned above traveled a total combined distance equivalent to traveling 12.35 times around the earth at the equator. To the closest mile, what is the radius of the earth? Use 3.14 as your approximation for pi.

Answered by Leeanne Boehm.
Books and cars 2001-02-13
From Aquilya:
  1. A pile of books is 96.08cm. If each book is 0.8cm thick. How many books are in th pile?

  2. 2. A car travels 9.84km on 0.6 litres of petrol. How far will the car travel on 3.7 litres of petrol?

Answered by Penny Nom.
Making milkshakes 2000-09-04
From Linda:
To make a chocolate milkshake, 3 parts chocolate syrup are mixed with 2 parts malt. To make a vanilla milkshake, 2 parts vanilla syrup are mixed with 1 part malt. If equal parts chocolate and vanilla milkshakes are mixed, what is the proportion of malt to milkshake?
Answered by Penny Nom.
Two word problems 2000-08-16
From Bridget:
A whale's head is 72 inches long... its tail is as long as its head plus half the length of its body, and its body is half the entire length. How long is the whale?

Also, An author published a book every two years. When the seventh one was published, the sum of the years of publication was 13,804. In what year was the author forst published?

Answered by Penny Nom.
Word problems 2000-03-31
From Amy:
  1. a north bound train left at noon. four hours later a south bound train left the same station. at 5 o'clook they were 160 miles apart. what was the rate of both if the north bound train was going 20 miles faster than the other one.
  2. clark's final exam was given 5 times the weight of the weight of a weekly test. the avgerage of 15 weekly test was 91. the overall weighted average was 85. what did he make on the final.

Answered by Penny Nom.
Two problems 2000-03-14
From Teresa Bostic :
  1. A man's age at death was 1/29 of the year of his birth. How old was he in 1949?
  2. At a contest, 2 persons were asked their ages. Then to test their ability mathematically, they were asked to give the ages together. One gave 44 and the other gave 1280. The first had subtracted one age from another, and the second had multiplied the two together. What were their ages?

Answered by Penny Nom.
Two problems 2000-01-29
From D. J. Anthony:

Hi, I am taking a course "math for elementary teachers" and I have two problems.

  1. How thick is a sheet of paper in your textbook.
  2. A little island has a population of 1,000 people. It doubles every 30 years. What will the population be in 30 years?, in 60 years?, when will it be over one million?

Answered by Peny Nom and Claude Tardif.
Missing the boat 1999-05-11
From Judith Moe:
Our daughter is in Grade 3 and seems stubbornly determined NOT to learn how to add and subtract. She's been assessed as quite intelligent in reading and writing,...Do you know of any alternative approaches to teaching/learning math that are proving useful in such circumstances.
Answered by Diane Hanson.
Extra point questions 1999-04-15
From W Troy Council:
My teacher has given me 5 extra point questions. I have figured out two, but i need a little assistance with 3 others, could you help me with:
  1. A stablehand agreed to work for 1 year. At the end of that time, she was to receive $240 and one horse. After 7 months she quit the job, but still received the horse and $100. What was the value of the horse?

  2. If the roots of x2 + bx + c are pi and square root 2, then find "b" and "c."

  3. ...

Answered by Penny Nom.
Two contest problems 1999-04-14
From Bruce Baldwin:
We have students that are preparing for the Pythagoras Contest which is a nation wide Grade 6 math challenge.

In the preparatory tests we have run into several questions that we can not understand.

Is there anyone who can help us?

  1. If 1 * 9 = 0, 9 * 8 = 72, 2 * 8 = 9, then 9 * 9 = ?

  2. ...

Answered by Judi McDonald and Walter Whiteley.
Word problems 1999-02-09
From Brian Rodriquez:
Please answer these problems with a formula. Also explain in English step by step how these problems should be solved. I know the answer I just don't know how the answer was achieved Thank you very much for trying to help
  1. A ski lift carries a skier up a slope at the rate of 120 feet per minute and he returns from the top to the bottom on a path parallel to the lift at an average rate of 2640 feet per minute. How long is the lift if the round trip traveling time is 20 minutes?
  2. An airplane on a search mission flies due east from an airport, turns and flies due west back to the airport. The plane cruises at 200 miles per hour when flying east, and 250 miles per hour when flying west. What is the farthest point from the airport the plane can reach if it can remain in the air for 9 hours?

Answered by Jack LeSage and Penny Nom.
Some Word Problems 1998-12-17
From Jennifer Rudd:
To Whom It May Concern,
I'm having some difficulty with these word problems. Maybe you could help. Thanks.
  1. A matte of uniform width is placed around a painting so that the area of the matted surface is twice the area of the painting. If the outside dimensions of the matte are 40cm and 60cm, find the width of the matte.

  2. The Joneses start out A 1520km car trip to Walker Park. On the first day they cover 960km. On the second day they complete the trip, but a rainstorm causes them reduce their average speed by 10km/h.If the 2-day trip took a total of 20 h, what was the average speed on each day?

  3. Granny stood up at her grandson's wedding reception and announced " My age now is a perfect square and it is equal to the difference between the square of my grandson's father's age and the square of his mother's age. Come to think of it the difference my age and the square of my grandson's age is seven times the age of his mother, my daughter in law." The grandson's wife remarked to her new husband," That means the difference between the squares of our ages is three times the age of your father!" How old was the bride?

  4. The volume of a retangular box 4cm high is 144 cubic cm. If the perimeter of the base is 24cm, find the dimensions of the box.
P.S. the first two questions are the most important ones that need to be solved.

Thanks for your help!!
Answered by Jack LeSage and Penny Nom.

Logic and Matrix Instruction 1998-04-24
From Robin Booker:
I need assistance with instruction strategies to teach the construction of a matrix, solving a logic problem. Providing instruction in the construction of a simple matrix , no problem. However, I stumpted on this one.

Five players were chosen as All Stars at the basketball banquet. Based on the following clues, find the player's name, team, uniform color and number of points scored....
Answered by Harley Weston.

Smith, Rodriguez and Jones 1996-11-07
From Rafayel Ambartsumyan:
On a train, Smith, Rodriguez, Jones are the fireman, brakeman, and engineer, but not in that order. Also aboard the train are three businessman who have the same names, a Mr. Smith, a Mr. Rodriguez, and a Mr. Jones. ..... Who is the engineer?
Answered by Penny Nom.
Grade nine problem solving 1996-03-11
From Azmat Hussain:
Can math problems be actually fun and engaging?
Answered by Diane Hanson.



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