Math question?

Question

This question was confusing to me. What is the ratio of the volume of the cylinder to the volume of the sphere?
A) 9:32
B) 3:8
C) 9:8
D) 1:2
E) 2:1
If you know how to do it, please tell me how you figured it out. Thanks a lot. =)

I'm soo sorry! I didn't mention the sizes..how dumb of me! The cylinder: radius=4, height=8
The sphere: radius=3

Thank you for those who reminded me to add the sizes . =)

Answer 1

Vol cylinder is 16π•8 = 128π
Vol sphere is 4/3 • 27π = 36π
ratio is 128π/36π = 32/9, which matches A if it's ratio of sphere to cylinder and not what you said.

Answer 2

You need more information. They either have to give you the radius and height or the type of cylinder.

volume of a cylinder = (pi)(r^2)(h)
volume of a sphere = (pi)(4/3)(r^3)
volume of a cylinder/volume of a sphere = (pi)(r^2)(h)/(pi)(4/3)(r^3) = 3h/4r
I'm thinking they told you that r = 2h for the cylinder, or something like that. In that case, the answer is B.

Answer 3

You'll haven't mentioned the size of the cylinder or the sphere.

Volume of Sphere = 4/3πr^3 (r given as 3)

= 108/3π = 36π

Volume of Cylinder = πr^2h (r given as 4, h given as 8)

= 128π

ratio is 128π:36π

= 128:36

= 32:9

Answer 4

ummmm....... it would help if I knew what size each were........

2:1
9:8
both say the cylinder is bigger

9:32
3:8
1:2
all say the sphere is bigger, and I can't help you anymore without knowing the exact sizes... sorry