SOLUTION: Two balls fit into a circular cylinder can. What is the radius of each ball if the volume of the can is 100π cm^3? Below the question is has a small picture of a rectangle

Algebra ->  Volume -> SOLUTION: Two balls fit into a circular cylinder can. What is the radius of each ball if the volume of the can is 100π cm^3? Below the question is has a small picture of a rectangle       Log On


   

Question 892668: Two balls fit into a circular cylinder can. What is the radius of each ball if the volume of the can is 100π cm^3?
Below the question is has a small picture of a rectangle with two circles in it. I'm having trouble explaining it, but Each ball touches the other ball, the side, and the top and bottom. I'm unsure as to whether or not that is important to the question.
Thanks!
Answer by josgarithmetic(39838) About Me  (Show Source):
You can put this solution on YOUR website!
Your picture indicates (your description) that the height h=4r.
The radius of the base is r.
Volume of the cylinder is h%2Api%2Ar%5E2, which is the base area multiplied by height h.

The value for the cylinder volume is given as 100pi.
Cylinder volume is then h%2Api%2Ar%5E2=100pi.
Substitute the expression for h:
highlight_green%284r%2Api%2Ar%5E2=100pi%29, and solve for r.

Solving steps:
r%5E3%2A4pi=100pi
r%5E3=%28100pi%29%2F%284pi%29
r%5E3=25
highlight%28r=25%5E%281%2F3%29%29, "cubed root of 25". You could also say highlight%28r=5%5E%282%2F3%29%29.

Value for r, highlight%28r=2.924%29 as an approximation.