posted by Mika .
A metal cylinder with a 4 inch radius and a 10 inch altitude is melted and recast into solid right circular cones each with a 1 inch radius and 2 inch altutudes. What is the number of cones formed?
Dig out your formulas for volume of cylinder and cone:
cylinder V=Bh = pi * r^2 * h = 160pi
cone: V = 1/3Bh = 1/3 pi r^2 * h = 2/3 pi
SO, 160/(2/3) = 240 cones.