Question

The radius and slant height of a cone are $5$cm and $20$cm respectively. Find its curved surface area.

Answer 1

Curved surface area of cone$=\pi rl$

where $r$ is the radius and $l$ is the slant height of the cone.

Given $r=5,l=20$

Therefore Curved surface area $=\pi \times 5\times 20$

$=3.14\times 5\times 20$

$=314$

Therefore Curved surface area $=314c{m}^2$