Question

From a solid cylinder of height 8 cm and radius 6 cm, a conical cavity of the same height and same radius is carved out. Find the total surface area of the remaining solid. (Take π = 3.14)

Answer 1

Given:

For Cylinder and cone Height = 8 cm

Radius = 6 cm

The slant height of the cane

⇒ BC² = BD² + DC²

= 8² + 6²

= 64 + 36

BC² = 100

BC = 10 cm.

Total surface area of remaining solid

CSA of cylinder + area of base + CSA of cone

= 2 πrh + πr² + πrl

= 2 × π × 6 × 8 + π × 6 × 6 + π × 6 × 10

= 96π + 36π + 60π

= 192π

= 192 × 3.14

= 602.88 cm²