Question

The volume of cylinder is $3960 \mathrm{~cm}^3$. Its curved surface area is $1320 \mathrm{~cm}^2$, then radius of the base of cylinder is___

Answer 1

Vol. of cylinder $=3960$
Surface area $=2 \pi r h$
$2 \pi r h=1320$
$ r h=\frac{1320 \times 7}{22 \times 2} $
$ r h=210$
$ \mathrm{Vol}=3960$
$ \pi r^2 h=3960 $
$ \pi r(r h)=3960 $
$\pi r(210)=3960 $
$ r=\frac{3960 \times 7}{22 \times 210}=6 \mathrm{~cm}$