How many spheres 12 cm in diameter can be made from a metallic cylinder of diameter 8 cm and height 90 cm?
Vol of cylinder = x×volume of sphere
πr2h = x ×43πR3
(429) = x × 43227 × 6×6×6
16 × 90 = x × 4×2×6×6
(16×904×2×6×6) = x
x = 5
5 spheres can be made out of this cylinder