The volume of a cone is equal to that of a cylinder whose height is 9 cm and diameter 60 cm. find the radius of the base of cone if its height is 108 cm.
- A. 12 cm
- B. 18 cm
- C. 10 cm
- D. 15 cm
Answer: D. 15 cm
Explanation: Cylinder volume = π × 30² × 9 = 8100π cm³. Cone volume = (1/3)π·R² × 108 = 36π·R³. Equating: 36π·R² = 8100π => R² = 225 => R = 15 cm.