







The volume of an attic 
20170907 

paul pose la question : trying to determine volume of an attic base is rectangular 29 ft by 37 ft
peak runs parallel to longest base side and is 7 ft long
roof lines run from each end of the peak to the respective corners
the peak is 3.5 ft above the base
(so seen from above there are 5 visible lines: the peak and 1 line to each of the 4 corners) Harley lui répond. 





A rectangle and a circle 
20170812 

Ramzan pose la question : a diagram shows the shape of rectangular framework with length (2x+20)cm and with (y+10)cm . The outline is made of wire . If a circle with diameter 56 cm is to be made from the wire and the area of the rectangle is 420 square centimeter ,find the possible lengths and width of the rectangle Penny Nom lui répond. 





Quadratic Equations 
20170328 

Natalie pose la question :
Hi Maths Central,
I am having trouble with quadratic equations. The question is:
Calculate the length 'l' of a rectangular pool by creating and solving a quadratic equation.
1. The rectangular pool is of equal area to a square pool, and a circular pool (5.70m^2).
2. The length of the rectangular pool must be 2m longer than the width 'w'.
Thank you so, so much for your help, Maths Central! Penny Nom lui répond. 





A block base for a plywood rectangle 
20170218 

Joe pose la question : How many cinder blocks 16x8 would i need to build a solid base for a plywood base 54inches wide and 30 inches deep Thank you Penny Nom lui répond. 





Angular speed 
20170121 

Kenzi pose la question : A wheel of radius 14 inches is rotating 45°/sec. What is the linear speed in in/sec and the
angular speed in RPM? (Round your answers to three decimal places)
I already found the linear speed. I got 10.996 in/sec. I don't know how to find the angular
speed. Penny Nom lui répond. 





The width of a 300 foot long rectangular acre 
20160921 

Debbie pose la question : If 2 sides of a 1 acre plot is 300 feet each what are the other 2 sides? The acre is a rectangle. Penny Nom lui répond. 





The distance around a warehouse 
20160921 

Chuck pose la question : How far do I walk when I walk around a 751,000 sq. ft. warehouse? Penny Nom lui répond. 





A trough with a triangular cross section 
20160521 

Clarice pose la question : 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? Penny Nom lui répond. 





The volume of a truncated rectangular pyramidal pond 
20160513 

Paul pose la question : 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 Harley Weston lui répond. 





A rectangular field 
20160507 

Jan pose la question : 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? Penny Nom lui répond. 





15.86 acres 
20160421 

Ronald pose la question : 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? Penny Nom lui répond. 





Sloping my yard away from my house 
20160415 

Harold pose la question : 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? Penny Nom lui répond. 





A rectangular prism 
20160302 

Paula pose la question : 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! Penny Nom lui répond. 





A rectangular enclosure 
20160115 

Amber pose la question : A rancher wants to use 300ft of fencing to enclose a rectangular area of 4400 square feet. What dimensions should the rectangle be? Penny Nom lui répond. 





A triangular shaped garden 
20160113 

Demetrie pose la question : Dwayne's garden is triangleshaped 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? Penny Nom lui répond. 





The perimeter of a triangular plot of land 
20160111 

Janelle pose la question : I need to fence off 6.5 acres. The plot is triangular shape. How many feet would I be fencing off? Penny Nom lui répond. 





Water flowing through a rectangular drain 
20160108 

Tiffany pose la question : 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? Penny Nom lui répond. 





Fencing around a rectangular field 
20151111 

Darlene pose la question : 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. Penny Nom lui répond. 





The surface area of a triangular prism 
20150603 

Alex pose la question : Find the surface area of a triangular prism with Isoceles triangles and dimensions 4 feet by 6 feet Penny Nom lui répond. 





Bearings and a rectangular plot 
20150214 

Mubashir pose la question : 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 Penny Nom lui répond. 





Revolutions per minute 
20141024 

Edward pose la question : 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 Penny Nom lui répond. 





A tennis ball in a triangular prism 
20141006 

Anna pose la question : 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! Penny Nom lui répond. 





A barge of triangular cross section 
20140818 

tushar pose la question : 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 Penny Nom lui répond. 





Angular speed 
20140629 

andrea pose la question : 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? Penny Nom lui répond. 





Two rectangular prisms 
20140410 

hannah pose la question : 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 Penny Nom lui répond. 





The surface area of a rectangular prism 
20140408 

Manraj pose la question : Find the surface area of a rectangular prism with dimensions 4, 5, and 7 units. Penny Nom lui répond. 





A rectangular shaped property 
20140117 

Donna pose la question : If I I have property that is rectangle shaped. I I know the ends are 100 feet how many feet would the sides be to make 5.4 acres Penny Nom lui répond. 





The area of an irregular octagon 
20131118 

zafar pose la question : if i have a rectangular octagon then how i can find its area
1. The length of rectangle is 42 and the width is 21 and and the base length is 4212 =30 i mean the
length of base =30 Penny Nom lui répond. 





A rectangular hyperbola 
20130919 

Soumya pose la question : Is the graph of an inverse variation a RECTANGULAR HYPERBOLA? If it is, then how can be the equation of a rectangular hyperbola be xy=constant , whereas in the books it is written that the graph of a rectangular hyperbola is x^2y^2=a^2? Chris Fisher lui répond. 





A gravel pile in the shape of a triangular pyramid 
20130404 

Casey pose la question : Hello
Right now I am stuck and I feel embarrassed because I feel like the answer is so easy I should know it.
I am working on a project and need to find a volume of gravel it will take to occupy this triangular prism like area. I am not sure what formulas I should use whether it be that for the volume of a pyramid or something more complex? Basically it forms a right triangle at one side then from there all points slope to one singular point about 10412mm away.
I am attaching a picture drawn up in paint with the actual dimensions to clear up any confusion.
Thank you for any help.
Casey Penny Nom lui répond. 





Question 
20130404 

Casey pose la question : Hello
Right now I am stuck and I feel embarrassed because I feel like the answer is so easy I should know it.
I am working on a project and need to find a volume of gravel it will take to occupy this triangular prism like area. I am not sure what formulas I should use whether it be that for the volume of a pyramid or something more complex? Basically it forms a right triangle at one side then from there all points slope to one singular point about 10412mm away.
I am attaching a picture drawn up in paint with the actual dimensions to clear up any confusion.
Thank you for any help.
Casey Penny Nom lui répond. 





A railroad embankment 
20130122 

clint pose la question : the pennsylvania railroad found it necessary,owing to land slides upon the roadbed,to reduce the angle of inclination of one bank of certain railway cut near pittsburgh,pa.,from an original angle of 45 degrees to a new angle of 30 degrees. the bank as it originally stood was 200 ft.long and had a slant length of 60 ft.. find the amount of the earth removed, if the top level of the bank remained unchanged. Penny Nom lui répond. 





Revolutions per second 
20121018 

Crystal pose la question : Suppose a car wheel is 26 inches in diameter.
a) If the tire completes one rotation, how far would the car travel?
b) If the car is traveling at 60 miles per hour, how fast is the car wheel spinning in revolutions per second? Penny Nom lui répond. 





Angular velocity 
20120905 

Kyra pose la question : A belt connects a pulley of radius 8cm to a pulley of radius 6cm. Each point on the belt is travelling at 24 cm/sec. Find the angular velocity of each pulley. Penny Nom lui répond. 





The volume of a wedge 
20120528 

olwethu pose la question : volume of wedge that have side 3,3 cm and 6,2 cm and 20 cm long? Penny Nom lui répond. 





A rectangular prism 
20120405 

Tori pose la question : How do you find the base height if the base width is 10ft. The height is 7ft. And the volume is105ft. Penny Nom lui répond. 





Triangular numbers that are square 
20111227 

Luke pose la question : The “TnS” is a positive integer which is both Triangular number
and Square number. For example, 36 is a “TnS” number
since 36=1+2+3+4+5+6+7+8 (Triangular number)
and 36=6x6 (Square number).
What is the next “TnS” which is greater than 36? Penny Nom lui répond. 





The volume of a triangular shaped aquarium 
20110507 

Jeff pose la question : HI, I searched the site but really couldn't find my answer,
at least that I could understand! I have a triangular shaped aquarium
( think of a cube, except its an equal triangle shape). all 3 sides are 48 inches,
and it is 34" tall. Can you please tell me what the volume is in gallons?
Thanks! Penny Nom lui répond. 





The volume of a triangular pyramid 
20110415 

Chelsea pose la question : There is a triangular pyramid which is an equilateral on the base with all sides 16.5 and the height is 25. I have to find the volume. Please help! Penny Nom lui répond. 





Slicing a rectangular parallelepiped 
20110223 

tom pose la question : a) Pass a plane containing a vertex of a rectangular parallelepiped and a
diagonal of a face not containing that vertex to cut a pyramid from the
parallelepiped. What fraction of the volume of the parallelepiped is the
volume of the pyramid thus cut off?
b)Pass a plane through a cube of edge 8 in so that the section formed
will be a regular hexagon. Through each side of the hexagon pass two
planes, one plane containing one of the two vertices of the cube
which are farthest away from the plane of the hexagon, the other
plane containing the diagonally opposite vertex of the cube. Find the
volume of the solid bounded by these planes.
c)three of the edges of a rectangular parallelepiped that meet in a point
are also the lateral edges of a pyramid. What fraction of the parallelepiped
is this pyramid...?
you know the my only problem is how to illustrate this one...if only i
could ...can you help me....all I need is the drawing and I can do the rest
..it's fine if you'll only answer any of these but I'll be thankful if you
will do the three :).... Penny Nom lui répond. 





Angular speed 
20101212 

Jason pose la question : 7 in. pulley traveling @ 175ft/sec. What is the rpm? Stephen La Rocque and Penny Nom lui répond. 





The length is twice its breadth 
20101209 

jenu pose la question : The length of the rectangular field is twice its breadth. A man jogged around it 5 times and covered a distance of 3 km. what is the length of the field? Penny Nom lui répond. 





A rectangular solid 
20101208 

ryan pose la question : Good day!
Have a question on rectangular solids. We were asked to find the dimensions of a rectangular solid, we were only given the volume of the rectangular solid, the total area, and the altitude. I tried using the volume of the rectangular solid and was able to get the area of the base, but I don't know how to get its length and its width. Hope you could help me again. Thanks! Penny Nom lui répond. 





Angular speed 
20101203 

Julie pose la question : If the angular speed of a circle is 360 degrees divided by the time it took to rotate,
how do I calculate ones that have greater rotations than the amount of time?
I mean, you calculate the angular speed of a merrygoaround that spins once every 5 seconds
by doing 360degrees/5 sec, but how do you calculate a merrygoaround that has 16 rotations every 4 seconds? Penny Nom lui répond. 





Rectangular arrays 
20100929 

Kim pose la question : My 4th grader has started working on rectangular array that shows 2 factors of a number.
The problem reads on centimeter grid paper draw as many arrays as you can for each of the #'s 2,3,4, 5,6,7,,11,12,15 and 16. That would be great except I have no idea what they are talking about and I cannot offer any help to my daughter. Penny Nom lui répond. 





An 18ft round pool 
20100719 

christine pose la question : will an 18ft round pool fit on a 12x16 ft rectangular cement slab? Tyler Wood lui répond. 





A rectangular prism 
20100427 

Savannah pose la question : A rectangular prism is made of exactly 8 cubes. Find
the length, width, and height. Penny Nom lui répond. 





What are the dimensions of the box? 
20100413 

Steven pose la question : The longest rod that will just fit inside a rectangular box,
if placed diagonally top to bottom, is 17 inches.
The box is 1 inch shorter and 3 inches longer than it is wide.
How much must you cut off the rod so that it will lie flat in the
bottom of the container? What are the dimensions of the box? Robert Dawson lui répond. 





Pyramids and parallelograms 
20100401 

Vivi pose la question : Hi, my name is Vivi, and math teacher is giving a geometry test. I tend to forget how to find the surface area and volume of triangular pyramids and parallelograms. Do you have a way of remembering how to find the surface area? Harley Weston lui répond. 





A champagne pyramid 
20100322 

Kathy pose la question : I have 680 champagne glasses and my pyramid can only be 15 levels high. How many glasses need to be on each level? Is there a formula I can use? Robert Dawson lui répond. 





Angular velocity 
20100317 

Lindsay pose la question : Determine the angular velocity, in radians per second, of a 14inch car wheel, if the car is traveling at 60 miles per hour Harley Weston lui répond. 





The base area of rectangular prism 
20100305 

Desiree pose la question : How do you find the base area of rectangular prism that has 4 cm by 4cm by 6cm ? Penny Nom lui répond. 





The center of a rectangular room 
20100216 

Diana pose la question : Consider a rectangular room, 15 feet wide, 30 feet long and 12 feet high. What is the exact distance from any of the 8 corners of the room and its geometric center? Can you write a generic formula for such a distance? And if we keep the same proportions on all dimensions, can you write an expression for the same distance as a function of the floor perimeter? Penny Nom lui répond. 





A triangular prism 
20100113 

Breon pose la question : what is the formula for a triangular prism? Robert Dawson lui répond. 





A triangular pyramid 
20100105 

ally pose la question : how many vertices, edges, faces in a triangular pyramid? Robert Dawson lui répond. 





Angular speed 
20091119 

Atalie pose la question : The engine of a sports car rotates at 5000 revolution per minute. Calculate the angular speed of the engine in radians per second, given that 2pi radians = 1 revolution Robert Dawson lui répond. 





A triangular shaped ditch 
20091112 

Tim pose la question : I am planning on constructing a triangular shaped ditch the measures 550 meters in length, 6 meters wide at the surface, .3048 meters at the invert of the ditch and 2 meters deep.
How many cubic meters of material will have to be excavated to construct
this ditch Robert Dawson lui répond. 





Angular speed 
20090804 

Mary pose la question : The engine of a sports car rotates at 5000 revolutions per minute (rpm). Calculate the angular speed of the engine in radians per second. Use 2 radians = 1 revolution. Penny Nom lui répond. 





The surface area of a rectangular pyramid 
20090713 

Shivani pose la question : What is the surface area of a rectangular pyramid with a length of 6 inches,
a width of 7 inches and a SLANT height of 4 inches. Penny Nom lui répond. 





Triangular Numbers 
20090616 

Chinonyerem pose la question : Question from Chinonyerem, a student:
Each of the numbers
1 = 1, 3 = 1+2, 6 = 1+2+3, 10 = 1+2+3+4 ,...
represents the number of dots that can be arranged evenly in an equilateral
triangle:
.
. . .
. . . . . ...
. . . . . . . . . .
This led the ancient Greeks to call a number TRIANGULAR if it is the
sum of consecutive integers, beginning with 1. Prove the following facts
concerning triangular numbers:
(a) A number is triangular if and only if it is of the form n(n+1)/2 for some n >= 1
(b) The integer n is a triangular number if and only if 8n+1 is a perfect square
(c) The sum of any two consecutive triangular numbers is a perfect square
(d) If n is a triangular number, then so are 9n+1, 25n+3, and 49n+6 Penny Nom lui répond. 





The dimensions of a toy chest 
20090507 

charlotta pose la question : My son needs to find the 3 dimensions of a toy chest that has to have a volume of 24 cubic feet can you show how to get the answer Penny Nom lui répond. 





Rectangular prisms 
20090501 

deborah pose la question : Could you please tell me some examples of different objects in the real world of rectangular prisms? Harley Weston lui répond. 





Volume of a prism 
20090421 

David pose la question : The base of a rectangular prism has an area of 15.3 square inches and a volume of 185.13 cubic inches. Write an equation that can be used to find the height "h" of the prism Robert Dawson and Stephen La Rocque lui répond. 





A rectangular open box 
20090321 

tina pose la question : An open box is to be made from a rectangular piece of tin by cutting two inches squares out of the corners and folding up the sides. The volume of the box will be 100 cubic inches. Find the dimensions of the rectangular piece of tin. Stephen La Rocque lui répond. 





A dead fly is stuck to a belt that passes over two pulleys 
20090321 

Jules pose la question : A dead fly is stuck to a belt that passes over two pulleys 6 inches and 8
inches in radius. Assuming no slippage,how fast is the fly moving when
the large pulley (8 inches) makes 21 revolutions per second ? How many
revolutions per second does the small pulley make ?
How long will it take the dead fly to travel 1 mile ? Penny Nom lui répond. 





A triangular pyramid 
20090226 

Craig pose la question : Can you help with this question:
Write the names of the faces and the number of each kind of face on a triangular
pyramid? Penny Nom lui répond. 





A rectangular prism 
20090225 

Christina pose la question : I am trying to find the area of the base of a rectangular prism where one cube=_1 cu in. The Answer is given in square inches. I also need the volume of the prism in cu in. For example length=3, w=2, h=5 Penny Nom lui répond. 





The surface area of a cube and rectangular prism 
20090216 

Mhiko pose la question : how to derived the total surface area of a cube and rectangular prism using geoboard?? Robert Dawson lui répond. 





Solid figures 
20090210 

Rebecca pose la question : I need to know the names of solid figures. I have several pictures that I need to answer what type they are.
Thanks, Rebecca 3rd grade Penny Nom lui répond. 





A triangular pyramid 
20090206 

kamran pose la question : what would be an example of a triangular pyramid Stephen La Rocque lui répond. 





Faces, edges and vertices 
20090204 

sheila pose la question : what is the relationship between the number of faces and the number of edges of a triangular pyramid ? Penny Nom lui répond. 





The volume of a prism 
20090119 

Mady pose la question : What is the general equation used to find the volume of a triangular prism? Robert Dawson and Harley Weston lui répond. 





A rectangular prism 
20090113 

nika pose la question : How many bases does a rectangular prism have? What are they? Harley Weston lui répond. 





Triangular prisms and pyramids 
20090110 

KJ pose la question : What are some items found in a home or school that could be considered a triangular prism or triangular pyramid? Robert Dawson and Penny Nom lui répond. 





A belt drives a pulley 
20081103 

Rebecca pose la question : A point on a belt is moving at the rate of 30 ft/sec and the belt drives a pulley at the rate of 200 rpm. What is the radius of the pulley? Penny Nom lui répond. 





Linear and Angular Velocity 
20081010 

Matthew pose la question : The pedal and gear relationship of a bicycle is shown. The radii of the gears are r(sub1) = 5 cm and r(sub2)= 12 cm. The radius of the wheel is r(sub3) = 30 cm. How many rotations per minute of the pedal gear will produce a racing cyclist's speed of 60 km per hr.
For a diagram: http://bikepedalsgears.weebly.com/ Stephen La Rocque lui répond. 





Angular & Linear Speed from a Sine Graph 
20080819 

Kim pose la question : Kim, a student:
I am given a graph with a wave. The amplitude is 5cm and the period is 4cm. I am suppose to find the angular speed. What I need to know is the formula for angular speed and how do I use these numbers to get the correct answer. Janice Cotcher lui répond. 





A triangular field 
20080815 

joneka pose la question : Barb walked five times aroun a triangle field all together she walked 435 feet the first side of the triangle fiel is 23 feet the length of the other two sides are of the same measure. What are the dimensions of the triangle field? Penny Nom lui répond. 





A rectangular room 
20080630 

Peter pose la question : A rectangular room has a perimeter of 42 feet and an area of 108 square feet. What is the length, in feet, of the shorter side? Penny Nom lui répond. 





Escort cards on a rectangular table 
20080613 

Susan pose la question : What size rectangular table will we need to put 230 2" X 3.5" escort cards on for my daughter's wedding reception with a spacing of .5 inch between them on all sides? Thanks so much for your help Penny Nom lui répond. 





The current in a river 
20080612 

Joi pose la question : To approximate the speed of the current of a river, a circular paddle wheel with radius 4 feet is lowered into the water. If the current causes the wheel to rotate at a speed of 10 revolutions per minute, what is the speed of the current? Express your answer in miles per hour. Harley Weston lui répond. 





An octagonal prism 
20080427 

Melanie pose la question : My son is identifying geometric shapes in the real world? We are stuck on octagonal prism, rectangular prism and square prism. Can you help me out with some examples. Thanks Penny Nom lui répond. 





A solid figure with 3 rectangular faces and 2 triangular faces 
20080417 

Emily pose la question : I am in the 3rd grade and my teacher gave us a question. What is a
solid figure with 3 rectangular faces and 2 triangular faces? Penny Nom lui répond. 





A rectangular prism 
20080331 

Chanlie pose la question : i need need to find a rectangular prism with a total surface area of 210 units. Penny Nom lui répond. 





Triangular prisms and pyramids 
20080303 

LORENA pose la question : hi i am in yr 6 and i need to know how many faces,vertices and edges these shapes have..
. TRIANGULAR PYRAMID
. TRIANGULAR PRISM Penny Nom lui répond. 





A square and an equilateral triangle 
20080210 

Emily pose la question : A square pen and a pen shaped like an equilateral triangle have equal perimeters. Find the length of the sides of each pen if the sides of the triangular pen are fifteen less than twice a side of the square pen. Stephen La Rocque lui répond. 





Radians 
20080208 

Brian pose la question : I'm teaching Precalculus right now and will be covering the formula to convert angular speed into linear speed. My question is about the units involved. Using v=rw, if r is mearsured in feet and w is measured in radians/second then v is measured in ft/sec. What happened to the units of radians? I can't find a good way to explain why they are not part of units for velocity. Do you have a good explanation?
Thanks, Stephen La Rocque lui répond. 





The surface area of the rectangular solid 
20071230 

Sara pose la question : For my math homework i found the volume of a rectangular solid whose deminsions were in feet and the numbers were 10 by 20 by 30
10 = hight
20 = short side base
30 = long side base
and now i have to find the surface area of the rectangular solid....
i know how to do this but i can't get the right answer
it should be 2,200 ft squared but i keep getting 13,00 feet squared Penny Nom lui répond. 





A rectangular prism 
20071116 

nicholas pose la question : What is the height the surface area to a rectangular prism with a volume of 350 milliliters? Stephen La Rocque lui répond. 





Radial motion 
20071113 

abdulai pose la question : a circular saw with diameter 18.4cm rotates at 2400rpm. What is the angular speed of a point on the edge of the saw blade in radians per second? Penny Nom lui répond. 





A triangular lot 
20071017 

Brian pose la question : Seeking the square footage of a triangular property lot, dimensions are: 620 X 620X 720. Penny Nom and Melanie Tyrer lui répond. 





Angular speed 
20070805 

Virginia pose la question : the engine of a sports car rotates at 5,000 revolutions per minute (rpm). calculate the angular speed of the engine in radians per second. use 2n radians = 1 revolution Stephen La Rocque lui répond. 





A triangular trough 
20070719 

janine pose la question : A trough is formed by nailing together, edge to edge, two boards 11 ft. in length, so that the right section is a right triangle. If a 15 gallon of water are poured into the trough and if the trough is held level so that a right section of water is an isosceles right triangle, how deep is the water? (231cu.in=1 gal.) Penny Nom lui répond. 





The area of a triangular pyramid 
20070718 

Jhezelle pose la question : What is the formula of finding the surface area of a triangular pyramid? Penny Nom lui répond. 





The number of blocks on the face of a pyramid 
20070627 

Heather pose la question : I was wondering if there was an equation in order to calculate the number of blocks on the face of a pyramid.
For example:
X
X X
X X X
Is there a specific formula in order to calculate that there are
6 blocks here?
Thank You,
Heather Harley Weston lui répond. 





What angle does the tire turn in 60s? 
20070604 

San pose la question : An automobile, travelling at 80km/h, is towing a trailer. The wheels of the trailer
are 40cm in diameter. Through what angle does the tire turn in 60second? Stephen La Rocque lui répond. 





The volume of a triangular prism 
20070601 

Hannah pose la question : How do I find the area of the base of a triangular prism, so that I can find the volume by using the equation on the attachment. The formula is that volume equals one half times (base times height) times triangle height. Thank you for your help.
Hannah Penny Nom lui répond. 





Angular velocity 
20070501 

Bruce pose la question : a tachometer of a Ford Explorer reads 2,100 rpm at 60 mph. Find the equivalent angular velocity in degrees per minute and radians per minute Stephen La Rocque lui répond. 





A beam on a lighthouse 
20070328 

Lisa pose la question : A beam on a lighthouse 2000 metres away from the nearest point P on a straight shoreline revolves at the rate of 10 pi radians per minute. How fast is the beam of the light moving along the shoreline when it is 500 metres from P? Stephen La Rocque lui répond. 





A triangular prism 
20070326 

Tom pose la question : Hi, I need to find a container in the shape of a triangular prism that will fit
four table tennis balls (this is for a math project!). These balls have a
diameter of 4cm, so a radius of 2. I know that the formula for finding
an incircle from a triangle is: radius of incircle =
2area of triangle / perimeter of triangle
But I need to know the length of one side of the triangle from the incircle
(the triangle needs to be equalateral).
Can you help me find a formula for this?
Thanks so much!
Tom Penny Nom lui répond. 





Surface area of a triangular prism 
20070221 

Katrina pose la question : What is the formula to finding the surface area of a triangular prism? Gabriel Potter lui répond. 





a specific 3d shape 
20070212 

Robby pose la question : What three dimensional shape has 6 vertices, 5 faces, and two congruent triangular bases? I can't find the answer to this question anywhere. Your help will be appreciated. Thanks, Robby Craig Pam Fowler, Gabe Potter and Walter Whiteley lui répond. 





Water in a triangular trough 
20070130 

Trina pose la question : the trough is 5 feet long and its vertical cross sections are inverted isosceles triangles with base 2 feet and height 3 feet. water is draining out of the trough at a rate of 2 cubic feet per minute. at any time t, let h be the depth and v be the volume of water in the trough. a. find the volume of water in the trough when it is full b. what is the rate of change in h at the instant when the trough is .25 full by volume? c. what is the rate of change in the area of the surface of the water at the instant when the trough is .25 full by volume? Penny Nom lui répond. 





Angular speed 
20070118 

Cristina pose la question : A car is moving at a rate of 50 miles per hour, and the diameter of its wheels is 2.5 feet. a) Find the number of revolutions per minute the wheels are rotating. b) Find the angular speed of the wheels in radians per minute. Stephen La Rocque lui répond. 





Angular speed 
20070106 

Robert pose la question : A rear wheel and tire on a John Deere 8520 farm tractor has a 39in. radius. Find the angle (in radians) through which a wheel rotates in 12 sec if the tractor is traveling at a speed of 22 mph. Penny Nom lui répond. 





1, 3, 6, 10... 
20061215 

Lisa pose la question : What is the nth term for the sequence, '1, 3, 6, 10...' and could you say how you got the anwser. Stephen La Rocque and Penny Nom lui répond. 





Pulleys and belts 
20061031 

Lynn pose la question :
A belt has a linear speed of 32 mph. It is spinning three pulleys. Pulley A has diameter 14 in. radius = 7 inches Pulley B has diameter 26 in. radius = 13 inches Pulley C has radius 3 ft. radius = 36 inches Angular speed in Radians per min for I got Pulley A= .08 rads/min Pulley B= .04 rads/min Pulley C=.01 rads/min How many cm would pulley C travel in 14 seconds? Penny Nom lui répond. 





The surface area of a triangular prism? 
20061029 

Amanda pose la question : What is the formula for the surface area of a triangular prism? Haley Ess lui répond. 





Angular speed 
20061004 

Jack pose la question : A horse on a merrygoround is 7m from the center and travels at a speed of 10km/h. What is its angular speed? Stephen La Rocque lui répond. 





A rectangular tank 
20060919 

Milton pose la question : What size rectangular tank will I need to hold 841.5 gallons of water. The water level is 3'0" from the bottom of tank. Penny Nom lui répond. 





The volume of a triangular box 
20060912 

Irene pose la question : How do I find the volume of a triangular box? Penny Nom lui répond. 





Angular velocity 
20060328 

Ben pose la question : How do you (a) express angular speed in terms of linear speed and (b) express linear speed in terms of angular speed? Stephen La Rocque lui répond. 





The volume & surface area of a rectangular pyramid. 
20060227 

Cheryl pose la question : My daughter is working on a math project & we are having a hard time finding the volume & surface area of a rectangular pyramid. Can you help us with this? Penny Nom lui répond. 





A triangle of 50p pieces 
20060222 

Stuart pose la question :
Ok, so i am collecting 50p pieces and arranging them on my desk in the shape of a triangle.
eg
50p
50p 50p
50p 50p 50p
50p 50p 50p 50p
I want to work out how much money I'm saving just by knowing how many rows of coins there are. If i can work out how many coins there are just by knowing how many rows I have I can just divide by 2 to find out the amount in dollars.
Penny Nom lui répond. 





Shapes 
20051112 

Tonya and Hailey pose la question : MY THIRD GRADERS TEACHER HAS SENT HOME HOMEWORK ASKING FOR THEM TO FIND REALWORLD OBJECT IN MANY DIFFERENTS SHAPES A FEW HAVE US STUMPED Penny Nom lui répond. 





A triangular pyramid 
20051022 

Stacee pose la question : When stacking oranges to form a triangular pyramid, each orange touching 3 oranges below it. In order to have a pyramid with 6 layers, how many oranges should be on the bottom layer? Penny Nom lui répond. 





A triangular lot 
20050521 

Linda pose la question : I am looking to purchase a piece of property, and I need some help trying
to figure out the square footage of the land. I know that
normally if I multiply the length and width I could get my answer. However,
this piece of land is an odd shape and has 3 measurements. Can you
please help me.
The measurements for this piece of land is:
97.8'
201.2'
139.7' Penny Nom lui répond. 





What is the name of a 3D rectangle? 
20040607 

Jack pose la question : if a cube is a 3D square, what is the name of a 3D rectangle? Penny Nom lui répond. 





Angular speed 
20040201 

Rachel pose la question : A 4 inch pulley on a motor makes 1500 revolutions/minute. It is connected to an 8 inch saw blade.
a. Find the angular speed of the pulley in radians/minute
b. Find the angular speed of the saw in radians/ minute
Harley Weston lui répond. 





A rectangular prism 
20030109 

Julie pose la question : How many faces on a rectangular prism and how many bases? Can the base also be a face and can a face also be a base? Diane Hanson lui répond. 





A triangular prism 
20021030 

Daniel pose la question : I was wondering what a triangular prism was. Diane Hanson lui répond. 





A triangular prism 
20020428 

A student pose la question : Need the formula for the surface area of a triangular prisim? Penny Nom lui répond. 





Triangular numbers 
20020426 

Anika pose la question : Can you please tell me what a triangular number is? Penny Nom lui répond. 





A triangular pyramid 
20010514 

Kumar pose la question : In a Pyramid OABC, all the three sides of the base: a, b, c are known. Also known are the angles between the three sides from the vertex O: Angles AOB, BOC, COA. With this information, is it possible to calculate the lengths of the three sides: OA, OB & OC. Chris Fisher lui répond. 





Prisms 
20010410 

A fourth grade class pose la question : A fourth grade class is curious about the names that have been given to various solid geometric figures based on their shapes: are there names for solids based on a rhombus, a trapezoid, a parallelogram, a decagon, and/or a quadralateral? Chris Fisher lui répond. 





Volume and surface area of a cylinder and a triangular prism 
20010331 

Kevin pose la question : I was wondering how do you find the volume and surface area of a cylinder and a triangular prism. Penny Nom lui répond. 





PreCalculus 
20000809 

Angela pose la question : Use absolute values to define the interval or pair of intervals on the real line.
<  ]    [ >
18 19 20 21 22 23 24 25 26
A car is moving at the rate of 50 miles per hour, and the diameter of its wheels is 2.5 feet. a) Find the number of revolutions per minute that the wheels are rotating. b) Find the angular speed of the wheels in radians per minute. Harley Weston lui répond. 





Angular velocity 
20000524 

Ashley Milliman pose la question : The crankshaft of a particular automobile engine has an angular velocity of 1,500 rpm at 30 mph. The crankshaft pulley has a diameter of 10 cm, and it's attached to an air conditioner compressor pulley with a 7 cm diameter and an alternator pulley with a 5 cm diamter At what angular velocities do the compressor and alternator turn? . . . Harley Weston lui répond. 





Triangular numbers and square numbers 
20000302 

Emily McCallum pose la question : Would someone find me some math activities using triangular numbers and square number. Especially acitivities that actually form the shapes. They need to be at the 5th grade or 6th grade level. But you can not find anything that can be tauht at these level, that fine. I just need to be able to teach this new subject or kind of math to my kids. Rick Seaman and Penny Nom lui répond. 





Pyramids and prisms 
20000118 

Tyler pose la question : What's the definition of a Triangular Prism and a Triangular pyramid. Penny Nom lui répond. 





Three dimensional rectangle 
20000111 

Dennis Murphy pose la question : I would like to find out the name of a Three dimensional rectangle. Harley Weston lui répond. 





Rectangular hyperbola 
19991215 

Aarti Chand pose la question : Why do they call a rectangular hyperbola, rectangular and where the normal hyperbola looks like a rectangle and the rectangular hyperbola looks like a sqaure? Chris Fisher lui répond. 





Cannonballs 
19990127 

Roger King pose la question : How many cannonballs can be stacked in a triangular pyramid? Penny Nom lui répond. 





Triangular Numbers 
19981030 

Matt pose la question : i would like to know about triangular numbers and it history i would also like to know about the history of prime numbers thank you Chris Fisher lui répond. 





Area and Volume 
19980728 

James Pulver pose la question : I am going into 12th grade and am practicing for the SAT II. I have come across a problem that I cannot solve. It states that the front, side , and bottom faces of a retangular solid have areas of 24 square centimeters, 8 square centimeters, and 3 square centimeters, respectively. What is the volume of the solid. I need to know how to solve similar problems so is there a formula to go from area to volume? Jack LeSage lui répond. 





Triangular Numbers. 
19970908 

Rachel pose la question : Show visually that the square number 16 is the sum of two triangular numbers. Which two? Penny Nom lui répond. 

