2018 · Q77
The lateral surface area of a cone is 462 {cm}². Its slant height is 35 cm. The radius of the base of the cone is
Elementary MathematicsMensuration
- A8.4 cm
- B6.5 cm
- C4.2 cm
- D3.2 cm
Explanation
Lateral surface area pi r l = 462 with slant height l = 35 cm. So r = 462/(35 pi) = 462/110 = 4.2 cm (using pi = 22/7). Hence option C.