Question

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

Answer 1

Given, Diameter $=70cm$ $\Rightarrow$ radius $r=35cm$

Curved surface area of a cone $=4070c{m}^2$

Since, curved surface area of cone $=\pi rl$

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

$\Rightarrow 4070\times \frac{7}{22}\times \frac{1}{35}=l$

$\Rightarrow l=37cm$

$\therefore$ slant height of cone $=37cm$