The curved surface area of a cylinder is 1320 cm
Question:

The curved surface area of a cylinder is 1320 cm2 and its base has diameter 21 cm. Find the volume of the cylinder.

Solution:

r cm = Radius of the cylinder

h cm = Height of the cylinder

Diameter of the cylinder is 21 cm. Thus, the radius is 10.5 cm.

Since the curved surface area has been known, we can calculate h by the equation given below:

The curved surface area of the cylinder = 2πrh

1320 cm2= 2πrh

$1320 \mathrm{~cm}^{2}=2 \times \frac{22}{7} \times(10.5 \mathrm{~cm}) \times h$

h = 20 cm

∴ Volume of the cylinder (V) = πr2h

$V=\frac{22}{7}(10.5 \mathrm{~cm})^{2}(20 \mathrm{~cm})$

= 6930 cm3