The radius of a cone is 3cm and vertical height is 4cm. Find the area of the curved surface.

Explanation

"radius of cone r `=3cm`
vertical height h`=
4cm`
so, l`=(r^2+h^2)^(1/2)`
`=(3^2+4^2)^(1/2)=5cm`

so curved surface area`=pirl`
`=pixx3xx5`
`=15picm^2`"