Question

The curved surface area of a cone is 4070 cm${}^2$ and its diameter is 70 cm. What is its slant height ?

Answer 1

$\pi rl=4070$

$r=35$

Therefore,

$\frac{22}{7}\times 35\times l=4070$

$l=37$ $cm$

Therefore, the slant height is $37$ cm.