Question

A cylinder labeled X has a height of 12 inches and a radius of 10 inches. Another cylinder labeled Y has a height of 36 inches and a radius of 30 inches.

The volume of cylinder Y is _______ times the volume of cylinder X.

Answer 1

I'm thinking 9????

Answer 2

Volume of cylinder X

V = pi*r^2*h

V = pi*10^2*12

V = 1200pi

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Volume of cylinder Y

V = pi*r^2*h

V = pi*30^2*36

V = 32400pi

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Ratio of volume of cylinder Y to volume of cylinder X = 32400pi/1200pi = 27


So The volume of cylinder Y is ___27____ times the volume of cylinder X.

Answer 3

As a shortcut, you can notice that each dimension in cylinder Y is 3 times the corresponding dimension in cylinder X. So the volume in cylinder Y will be 3^3 = 27 times greater than cylinder X.

Answer 4

Thanks, I had no idea what to do :) now it's easier to understand

Answer 5

that's great :)