Question

Find the curved surface area of a cone with base radius $5.25cm$ and slant height $10cm.$

Answer 1

Radius of base of cone $\left(r\right)=5.25cm$

and, slant height $\left(l\right)=10cm$

$\therefore$ Curved surface area $=\pi rl$

$=\frac{22}{7}\times 5.25\times 10$

$=\frac{22}{7}\times 52.5$

$=22\times 7.5$

$=165.0$

$=165c{m}^2$