Question

What is volume of a cylinder with base area 64pi cm2 and a height equal to twice the radius? Give your answer in terms of pi.

a
1024 pi
b
4096 pi
c
256 pi
d
512 pi

Answer 1

a 1024

Explanation:

To find the base area it is pi r^2, so work backwards 64pi = pir^2. Divide both sides by pi to cancel and you have 64=r^2, square root both sides and you get r=8. Using the radius to find the height you then multiply 8 by 2 so the height is 16. The formula to find Volume of a Cylinder is V= Bh, B=64 h=16.

So it equals 1024