Question

Curved surface area of a cone is $308c{m}^2$ and its slant height is $14cm$. Find
(i) radius of the base and
(ii) total surface area of the cone.

Answer 1

Given:Curved surface area of cone$=308$sq.cm

$\Rightarrow \pi rl=308$

$\Rightarrow \frac{22}{7}\times r\times 14=308$

$\Rightarrow r=\frac{308}{2\times 22}=7$cm

$\therefore$the radius of the circular end of the cone is $7$cm.

$\left(ii\right)$Total surface area of cone$=\pi r(l+r)$

$=\frac{22}{7}\times 7\times (14+7)=\frac{22}{7}\times 7\times 21=462{cm}^2$

$\therefore ,$ the total surface area of the cone is $462{cm}^2$