Three identical balls fit snugly into a cylindrical can: the radius of the spheres equals the radius of the can, and the balls just touch the bottom and the top of the can. If the formula for the volume of a sphere is V=4/3(pi)r^3, what fraction of the volume of the can is taken up by the balls?
Volume of one sphere = 4/3 *pi*r^3
Volume of 3 spheres is = 4 *pi*r^3
Volume of cylinder is pi*r^2 h
Here h is 6 r as balls fit snugly into cylinder
Therefore vol of 3 spheres / vol of cylinder = 4/6 = 2/3
Answer = [spoiler]2/3[/spoiler]
