Question

The radius of a cone is 5 cm and vertical height is 12 cm. Find the area of the curved surface. 

Answer 1

Given,
Radius of cone = 5cm = r
Height of a cone =12cm=h 

Slant height of the cone= `sqrt(r^2+h^2)`    

`= sqrt(5^2+12^2)=13cm` 

∴Curved surface Area = `pirl` 

`=22/7xx5xx12` 

= `204.28cm^2`