A solid metallic sphere of radius 18 cm is melted and recast into a cylinder of radius 9 cm. What is the height of this cylinder?

85 cm 72 cm 74 cm 96 cm

96 cm

Volume remains same for both figure ⇒ volume of sphere = volume of cylinder ⇒ \(\frac{4}{3}\) \(\pi \)r3 =  \(\pi \)r22h ⇒ \(\frac{4}{3}\) \(\pi \)(18)3 =  \(\pi \)(9)2h ⇒ 4 × 6 × (18)² =  (9)2h ⇒ h = \(\frac{7776}{81}\) = 96 cm