Question

The curved surface area of a right circular cone of height 15 cm and base diameter 16 cm is

Options

• 60π cm²

• 68π cm²

• 120π cm²

• `136 pi cm^3`

Answer 1

Height,

`h = 15 cm,`

`r= 16/2`

 `= 8 cm`

`l = sqrt(r^2 + h^2)`

`= sqrt(8^2 + 15^2)`

`= sqrt(64 + 225)`

`=sqrt289`

`l = 17 cm`

The C.S.A. of cone

`= pirl`

`=pi xx 8 xx 17`

`=136 pi cm^3`