







Finding the area of a regular polygon 
20070504 

From Dana: We are trying to figure the square footage of a tetradecagon....sort of a round house with 14 sides that are 8 ft' in length. It has a height of 9 ft. How do we figure the square footage of this? Answered by Stephen La Rocque. 





A volume expression for a pyramid 
20180423 

From Shaheer: Do a three sided pyramid and a square pyramid have the same formula if you want to calculate the volume? Answered by Penny Nom. 





A penny is thrown from the top of a building 
20180316 

From Zoraida: A penny is thrown from the top of a 26.7meter building and hits the ground 3.39 seconds after it was thrown. The penny reached its maximum height above the ground 0.89 seconds after it was thrown.
a. Define a quadratic function, h, that expresses the height of the penny above the ground (measured in meters) as a function of the number of seconds elapsed since the penny was thrown, t.
b. What is the maximum height of the penny above the ground? Answered by Penny Nom. 





Is a rectangle a parallelogram? 
20180228 

From ellie: is a rectangle a parallelogram? Answered by Penny Nom. 





Needing the area of an irregular Pentagon 
20171206 

From Dale: I'm needing to find the square footage of an irregular pentagon.
I've seen the other questions similar to this one, but without a great deal of difficulty can't get you the angle degrees, or the length between opposing angles.
I'm hoping that a different bit of information can help. So here goes:
The longest side is 67ft long.
One of its legs is 39ft long, and the other is 18ft long.
The leg off of the other end of the 39ft leg is 35ft long.
The leg off of the other end of the 18ft is 49ft long, and meets the other end of the 35ft side.
The information that I DO have, which I'm hoping makes the difference, is that the 39ft and the 18ft sides are parallel.
Also, while the angles at each end of the 67ft side are not right angles, they are fairly close to it,
approximately 80 degrees at the 39 ft side corner, and 100 degrees at the 18ft side corner.
Dale. Answered by Harley Weston. 





The surface area of a hexagonal pyramid 
20170616 

From Emilie: Hello, I need help with this question:
A pyramid has a regular hexagonal base with side lengths of 4 and a slant height of 6. Find the total area of the pyramid.
Thank you in advance if you can help me... Answered by Penny Nom. 





Building a pyramid 
20161201 

From Jesse: I'm trying to build a 30"by30"by 18.25"tall pyramid,what should my cutting measurements be? Answered by Harley Weston. 





A mixed number as a percent 
20161018 

From Jayda: how go you change a mixed number into a percent
Ex. 3 3/4 Answered by Penny Nom. 





The degree of 2x + 7 
20161017 

From Deejay: How about when the given has no degree and the other has a constant only, For example 2x + 7,
where's the leading term and what is its leading coefficient? Answered by Penny Nom. 





The number of sides of a polygon 
20160723 

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 volume of a truncated rectangular pyramidal pond 
20160513 

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 remeasuring the top perimeter.
Thanks,
Paul Answered by Harley Weston. 





Setting up a pool 
20160409 

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. 





The last two digits of a phone number 
20160403 

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. 





A rectangular prism 
20160302 

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. 





A word problem 
20160227 

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. 





Converting a fraction to a percentage 
20160222 

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. 





The diagonals of a polygon 
20160129 

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 
20160128 

From Hanna: The consecutive angles of a parallelogram measures Answered by Penny Nom. 





The height of a parabolic arc 
20151230 

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. 





The distance over a Quonset 
20150820 

From jane: total base of hemisphere is 30 ft
apex height is 20 feet
what is total length over dome Answered by Penny Nom. 





Parallelogram area 
20150804 

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. 





A pentagon inscribed in a circle 
20150530 

From Victoria: find the area of a regular pentagon inscribed in a circle with radius 3 units Answered by Penny Nom. 





The intersection of a plane and a cone 
20150516 

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. 





Filling a pool with dirt 
20150501 

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. 





A piecewise function 
20150425 

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. 





A tangent to y=x^3 passes through (0,2) 
20150405 

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 units digit of a prime 
20150108 

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. 





The degree of a polynomial 
20150105 

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^710m^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. 





An arithmetic progression 
20141119 

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. 





The grade of a road as a percent 
20140214 

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. 





The weight of a pipe full of water 
20130116 

From joe: how do you figure out the weight of a pipe full of water Answered by Harley Weston. 





Changing a decimal or a number to a percent 
20120810 

From Kenneth: When a decimal or a number is changed to a percent, the decimal or number is multiplied by 100 and then a percent sign (%) is attached.
Why is it necessary to multiply by 100?
What is the reasoning or logic for using this calculation? Answered by Robert Dawson. 





Profit as a percent 
20120414 

From Anson: The cost price of a CD is $50 and its marked price is $105. If the
selling price is $88, find the profit percent. Answered by Penny Nom. 





Expressing 0.5% 
20120206 

From Kenneth: Hello:
It is correct to express 0.5% as 5 tenths of one percent.
Is it also correct to express 0.5% as 5 tenths of onehundred percentage points or 5 tenths of one percentage point?
I think it would be 5 tenths of one percentage point because 5 tenths of onehundred percentage points would be 50 percentage points, but I'm not sure.
I thank you for your reply. Answered by Penny Nom. 





Two line segments in the plane 
20110815 

From Tim: For this problem I actually have tried to visualise the image in my head many times. This question makes my head spin.
Four points lie in a plane. They are partitioned into two pairs so that the sum of the lengths of the segments joining the points of each pair has the minimal possible value.
Prove that these segments have no common points. Answered by Chris Fisher. 





Dividing a polygon into triangles 
20110416 

From Foxie: You have a given regular polygon with n vertices and you divide it into triangles(using the vertices of the polygon) which each share at least one side with the polygon. How many distinct ways can you divide the polygon if its vertices are numbered? For n=3 it's 1 way, for n=4 it's 2 ways for n=5 5 ways, I'm not quite sure but think that for n=6 it's 12 ways... thanks in advance! Answered by Claude Tardif. 





Profit as a percent 
20101219 

From gaurav: In the following, which calculation is right to calculate the profit percent.
if profit is 20% 100*1.2 = 120
if profit is 20% 100/0.8 = 125? Answered by Penny Nom. 





The area of a polygon 
20100328 

From John: Question from John, a student:
How do you find the area of a polygon with any given amount of sides? Answered by Harley Weston. 





Cables in a pipe 
20091113 

From john: how many 0.28 mm diameter cables will fit into a 19.05 mm diameter pipe Answered by Stephen La Rocque. 





Cutting a pipe at an arbitrary angle 
20091024 

From Carol: I have read your article on cutting pipe,etc. at a 45 degree angle. I need to develop
an equation and pattern for cutting any size pipe (3" to 7") to any degree. I don't
understand how to transfer the wave pattern to graph paper.
Thanks. Answered by Harley Weston. 





A circle tangent to a line and with its centre on another line 
20081101 

From liza: Find the equation of the circle of radius squareroot 26 tangent to the line 5x+y=13 and having its center on the line 3x+y+7=0. Answered by Chris Fisher. 





The vertex of a parabola 
20080930 

From Anne: How do you find the vertex of the function f(x)=x squared+7x6 Answered by Penny Nom. 





Cutting a pipe on a 45 degree angle 
20080912 

From Bakshani: how do you a mark a pipe 5 inch diameter and cut it to form a 45 degree angel Answered by Stephen La Rocque. 





Liquid in a pipe 
20070905 

From christian: how many cubic feet are in a pipe that is 3" (inside diameter) and 459 feet long? Answered by Stephen la Rocque. 





The area for a pentagon 
20070209 

From nicole: how do you find the area for a pentagon Answered by Stephen La Rocque. 





What is the point of intersection of two sides of a polygon? 
20070123 

From Tyler: What is the point of intersection of two sides of a polygon? Answered by Stephen La Rocque. 





Calculating a person's volume 
20070120 

From James: Hi i am currently trying to calculate my volume. I have tried to do this using a tank of water and measuring the difference. i worked out that my volume is 112 litres. my question is that i want to make a box that would hold my volume and so i need to convert it into centimeters. i know that there are 100 cm^2 in a litre. if i divide this by 4 i would be 91x91x91ft. is this simply to do with density. if so how could i make this more realistic? Answered by Stephen La Rocque. 





The volume of a frustum of a pyramid 
20070117 

From Sam: Find the volume of a frustum of a pyramid with square base of side b, square top of side a, and height h. Answered by Penny Nom. 





Making a pyramid 
20040912 

From Jacob: My name is Jacob and I am a 11th grade student trying to build a pyramid for a friend but I need a chart of some sort to show me the measurements (I learn better w\pictures) it is a square base with 18 in sides and I want the vertex to be 18in above the base I need to know as many measurements as you can give me. Answered by Penny Nom. 





Construct a pentagon 
20021212 

From Mary: We were wondering what the instructions/formula, stepbystep, is to make a pentagon. Answered by Chris Fisher and Penny Nom. 





The shortest distance from a point to a line 
20010605 

From Kat: Find the shortest distance from the given line. Round to the nearest tenth. (2,1) and x+5y+20=0 Answered by Penny Nom. 





Typing a project 
20010501 

From Tom: Two students have to type a project. One can do it in 2 hours. It would take the other student three hours. They have 2 type writers. How fast can they finish by working simultaneously? Answered by Claude Tardif. 





Parabola problems 
20010410 

From Kathleen:
 Graph each function and state its domain and range. y = 3x^{2} + 4
 For each parabola find: i) the direction of opening
ii) the coordinates of the vertex iii) the yintercept iv) the xintercepts y = x^{2} + 3
 Find the equation of each parabola vertex at (0, 2) and passing through the point (3,7)
Answered by Harley Weston. 





Fractions 
20030510 

From Jacques: Voici la question qu'il pose: 2 x (1/2+1/4) + 3 + 2 x (1/31/4). La reponse est 4 2/3. Pourriez m'expliquer etapes par etapes ce que je dois faire. Answered by Claude Tardif et Diane Hanson. 





la pantographie 
19991118 

From Erick et Christine: Nous recherchons la définition de pantographie voltaïque, que représente cette "figure" ? estce qu'on peut en définir une unité de mesure ? Answered by Claude Tardif. 

