Question

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

Answer 1

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 cm²= 2 x 22 x (10.5 cm) x h
​                       7
h = 20 cm

∴ Volume of the cylinder (V) = πr²h
V = 22(10.5 cm)²(20 cm)
        7
V = 6930 cm³