







The inside diameter of a silo 
20170228 

JOHN pose la question : I need to find the inside diameter of a cement silo with an outside circumference
118 ft and a wall thickness of 7 inches. thank you John Kerr. Penny Nom lui répond. 





The diameter of the top of a truncated cone 
20160124 

Peter pose la question : 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" Penny Nom lui répond. 





A diameter of a circle 
20151227 

sahil pose la question : Find the equation of diameter of circle x2 +y26x +2y8 which passes through the origin. Penny Nom lui répond. 





The diameter and circumference of a circle 
20150901 

Tracey pose la question : 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! Penny Nom lui répond. 





How does pir^2 = 1/4pid^2? 
20141014 

al pose la question : Hi I cant work out the algebra. How does pir^2 = 1/4pid^2 Thanx Penny Nom lui répond. 





Cutting a hexagon from a disk 
20140405 

Paul pose la question : 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? Penny Nom lui répond. 





The diameter of the base of a cone 
20140223 

elwin pose la question : 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. Harley Weston lui répond. 





The circumference and area of a circle 
20111213 

Mable pose la question : A circle that going 70mi across using 22/7 I need the area,radius, and the circumference
and how to set up the steps can you help? Penny Nom lui répond. 





The diameter of a cake 
20110606 

nurul pose la question : Best Bakery shop received an order from your school to bake a 5kg of round cake for teachers day celebration. if a kilogram of cake has a volume of 3800cm^3,and the height of cake is to be 7.0cm, calculate the diameter of the baking tray to be used to fit the 5kg cake ordered by your school?(used pai=3.142) Penny Nom lui répond. 





The perimeter of a semicircle 
20110129 

Keith pose la question : I have the perimeter of a semi circle of 37 but how do I calculate the diameter from this.
This is all the information I have. Penny Nom lui répond. 





The diameter of a cylinder 
20110118 

Gayle pose la question : Given a cylindrical container that holds 45 imp. gallons and is 42 inches high, find the diameter Penny Nom lui répond. 





The diameter of a circle 
20100624 

John pose la question : Piece of wire 72cm in length bent to make semicircle and diameter.Find
length of diameter.Answer given 28cm.How is this arrived at?Looked at
circumference in various ways but failed to understand how 28 cm was
arrived at.Thanks for the help. Robert Dawson lui répond. 





The diameter of a circle 
20100430 

Jimmy pose la question : If I have a straight line with a known length and decide to make a circle out of this know length how would I calculate what the diameter of the circle would be Penny Nom lui répond. 





A truncated cone 
20091111 

Lucian pose la question : I need to calculate the bottom inside diameter of a truncated cone.
The top insdie diameter is 1450mm.
The material is 6mm thick
The cone angle is 20 degrees
The slant length is 152mm
I would like a formula so that I can build a spread sheet Penny Nom lui répond. 





Height of a Flag Pole 
20090626 

Jake pose la question : Can anyone answer this I am very stumped.
The flagpole on the roof of a Chocolate Factory is 13 cm in diameter and
a perfect cylinder. If one end of a 2300cmlong string is attached to the top
of the flagpole, and wraps around the flagpole exactly 16 times before ending
at the bottom of the flagpole, how tall is the flagpole? Need answer by Wednesday Penny Nom lui répond. 





A 27 inch diameter octagon 
20090404 

Gary pose la question : I am trying to build an octagon with 27 in outside diameter, i could make it 28 if it makes the calculations easier. Anyway i need to figure out the length of each individual piece of the octagon. I have tried and i can't get it, please help
Thanks Gary Harley Weston lui répond. 





The diameter of a roll of plastic 
20090324 

truong pose la question : hi. i have trouble to calculate the diameter of the plastic roll. the sheet is 765 m long and 0.8 mm to wrap around the core 400 mm in dia. please help me with the formula to calculate the dia of plastic roll, thanks in advance Harley Weston lui répond. 





A circular plaque in a square box 
20081128 

kmart pose la question : A square box has a diagonal of length 640cm.It is to contain a circular wall plaque. What is the
approximate diameter of the largest wall plaque that can be placed in the box? Penny Nom lui répond. 





The diameter of a circle 
20081101 

lupito pose la question : a circle has a 30`sector,33pi.find the diameter of the circle.How do I set the equation up. Victoria West lui répond. 





A roll of film 
20081016 

John pose la question : I need to know how to calculate the build up on a roll of film is calculated.
Example: I start with a 6" diameter core, and I start winding .005" thick film on the core, so I am adding a total of .010" to the diameter each wrap.
If I continue to do this for a total length of film of 3000 feet, what will the roll diameter be?
So what I need is the formula to perform this type of calculation.
Can you help me? I want to be able to plug the formula in a spread sheet and to be able to input a core diameter, a film thickness and a total length and get a roll diameter. Penny Nom lui répond. 





The sides of an octagon 
20080921 

mark pose la question : I need to know the measurements of an octagon with a inside diameter of 34.5 inches from side to side Penny Nom lui répond. 





The diameter of a sphere 
20080615 

Scott pose la question : The volume of a sphere is 6000cm cubed. What is the diameter of the sphere? Penny Nom lui répond. 





The sides of an octagon 
20080507 

Frank pose la question : Question from Frank, a parent:
Hi,
Need to lay out a 10 ft. diameter octagon on the ground. What is the
length of the
sides ? And the angles ? Harley Weston lui répond. 





The diameter of a circle 
20080428 

Mary pose la question : What is the diameter of a circle if the area is 132.7 square meters? I have tried the formula C=2 times pi radius and came up up 21.1. I also tried C = pi times d and came up with 42.26. The answer in the book says 13. How did they get this answer? Thank you for your help. Penny Nom lui répond. 





The diameter of a circle 
20080303 

Kathie pose la question : I know the length of the curved portion of a semicircle is 200 ft. but I need to find the diameter to get a total perimeter and area. How do I find the diameter to get the perimeter? Penny Nom lui répond. 





A radius and a tangent to a circle 
20071204 

elizabeth pose la question : show that the radius of a circle meets a tangent line to the circle in a 90 degree angle.
hint: start by assuming they are not perpendicular and at a contradiction. Penny Nom lui répond. 





The diameter of a gasket 
20071201 

Jorge pose la question : I have an application where I am using a circular silicone gasket. I have the total length but would like to calculate the diameter with the given length. What formula should be used? We receive these gaskets in a roll and cut them about 21 inches and glue the ends together to make it one piece. I would prefer to purchase these already cut and glued but require a diameter. If I had the overall diameter from a 21 inch length gasket, I can look online for a part that comes close to the diameter.
Jorge Harley Weston lui répond. 





The diameter of an octagon 
20071012 

Lewis pose la question : How do I calculate the dimension of the diameter of an Octagon when each leg has a dimension of 60 feet? Penny Nom lui répond. 





Diameter of an octagon 
20070807 

Bree pose la question : I am trying to find the diameter of a octagon with 20' sides . What formula do I use? Stephen La Rocque lui répond. 





Area of a circular garden 
20070618 

Cynthia pose la question : Hi is this the correct formula for this problem?
What is the approximate area of a circular garden that is 20 feet in
diameters? Stephen La Rocque lui répond. 





Swimming pool water 
20070412 

tina pose la question : How much water does a 24' round, 4' deep swimming pool hold? Haley Ess lui répond. 





What is the diameter of the planet? 
20061207 

Niall pose la question : In April 2005, scientists claimed to have captured light from an extrasolar planet orbiting a brown dwarf in the constellation Hydra some 230 lightyears from Earth. The scientists believe the planet is about five times the mass of Jupiter.
Assume the planet has the same density as Jupiter. What is the diameter of the planet? Stephen La Rocque lui répond. 





How do I calculate the roll diameter? 
20061105 

Bob pose la question : if I have the RPM of the roll and the thickness of the web coming off the roll and the mm/min of the web how do I calculate the roll diameter? Stephen La Rocque lui répond. 





Find the radius knowing the chord length and... 
20060728 

Jim pose la question : If I know the length of a chord and its distance from the diameter, how do I calculate the radius of the circle?
Stephen La Rocque lui répond. 





A 9 foot diameter circle 
20060702 

Lisa pose la question : How do I calculate 9 foot diameter measurement in total feet?? Stephen La Rocque lui répond. 





The length of the diameter 
20060518 

Steven pose la question : A circle has a circumference of 312in. Find the length of its diameter to the nearest integer? Penny Nom lui répond. 





The diameter of a pipe 
20060127 

An other pose la question :
I know the base length of my arc (10 inches)  I also know the height at the center to the arc (2 inches). I don't think the end is at the midpoint tho. How do I figure out how long the arc length is?
My question involves being able to cut a round pipe into an arc that is 10 inches wide and 2 inches tall. I need to know the smallest diameter pipe to buy in order to fulfill these requirements.
Penny Nom lui répond. 





The circumference of a larger circle is twice the circumference of a smaller circle. 
20060120 

Amanda pose la question : The circumference of a larger circle is twice the circumference of a smaller circle. What is the ratio of the radius of the smaller circle to the diameter of the larger circle? Penny Nom lui répond. 





The diameter of a 800 km circle 
20050122 

Mechelle pose la question : What is the diameter of a 800 km circle? Penny Nom lui répond. 





Circumference 
20030509 

A parent pose la question : Find the circumference use 3 1/7 for pi
1. r= 28 ft. 2. D=98 cm Penny Nom lui répond. 





Wrap a rope around the equator 
20030212 

Ali pose la question : If you take a rope and wrap it around the equator and then overlap it 6ft. and cut off the extra then you loosen it up so the ends meet how far would it stand off the ground? Penny Nom lui répond. 





What really is pi? 
20020905 

Rachel pose la question : what really is pi? 3.1444 Penny Nom lui répond. 





The circumference of a 72 
20020814 

Linda pose la question : What is the circumference of a 72" diameter circle? Penny Nom lui répond. 





Diameter of a pipe 
20020216 

Landry pose la question : I am trying to calculate the dia. of a pipe 60 inches long that will hold a gallon of water. What is the formula? Penny Nom lui répond. 





The distance across a circle 
20020118 

Douglas pose la question : If you know how far around a circle is (say earth) 25000 miles how do you calculate the distance across? Penny Nom lui répond. 





The diameter of an oval 
20010523 

Tim pose la question : Is there a such thing as a diameter of a oval? If not, is there a way to get the circumference? Claude Tardif and Penny Nom lui répond. 





A chord length 
20001017 

Al Paas pose la question : How to determine the length of a chord given the diameter of the circle and the maximum distance from the chord to The circle? Chris Fisher lui répond. 





The circumference of a circle 
19991005 

Mara Frost pose la question : what is the formula to find the circumference of a circle, or if there is no formula, how do you find the circumference of a circle? Penny Nom lui répond. 





Circles 
19990421 

Alex Elkins pose la question : How do you find the circumference of a circle if you only know the radius and the square feet or inches of the circle if the radius is 18 inches, If done in inches do you multiply by 12 to get the square feet? Jack Lesage and Harley Weston lui répond. 





A Hexagon 
19980922 

Lee Curtis pose la question : Could someone calculate this for me? If a hexagon is 38 feet 8 inches across, how wide would each of the six sides be? Thank you, Lee Curtis Chris Fisher and Harley Weston lui répond. 





Pi 
19971031 

Ryan McKinnon pose la question : What Is Pi? Chris Fisher lui répond. 





The diameter of the sun. 
19961029 

Lynda Mow pose la question : What is the process for solving the following question? As viewed from earth, the sun subtends an angle of approx 32'. If the sun is 93,000,000 miles from earth, find the diameter of the sun. Penny Nom lui répond. 

