A solid metal cylinder with a 4-in. radius and a 10-in. altitude is melted and recast into solid right circular cones each with a 1-in. radius and a 2-in. altitude. The number of cones formed is

Answer 1

vol of cyl = πr^2h = 160π
vol of cone = π/3r^2h = 2π/3

160π / (2π/3) = 240 cones

Answer 2

4^2*pi*10/1^2*pi*2 = 80