Question

A cone of radius $3cm$, has $CSA47.1c{m}^2$. Find volume.

Answer 1

$CSA=47.1c{m}^2$

$\pi rl=47.1$

$r=3cm$

$3.14X3Xl=47.1$

$l=\frac{47.1}{3.14X3}$

$l=5cm$

$v=\frac{1}{3}\pi X{r}^{2}Xh$

$h=\sqrt{(}{l}^2-r^2)$

$h=\sqrt{(}{5}^2-3^2)$

$h=\sqrt{1}6$

$h=4cm$

$V=\frac{1}{3}X3.14X{3}^{2}X4$

$V=37.68cm2$