2021 · Q37
A metal solid cube of side 22 cm is melted to make a cone of height 21 cm. What is the radius of the base of the cone? (Take π = 22/7)
Elementary MathematicsMensuration
- A11 cm
- B16.5 cm
- C22 cm
- D27.5 cm
Explanation
Equating volumes: 22³ = (1/3)πr²·21, so 7πr² = 10648. With π = 22/7, r² = 10648/22 = 484, giving r = 22 cm. Hence option C.