Question

The outer radius of a hollow cylinder is 3 cm and inner radius is 2 cm. If the height of cylinder is 7 cm, then the volume of cylinder is :

Answer 1

Find the volume of the cylinder with radius = 3 cm

Volume = πr²h

Volume = π(3)²(7) = 63π cm³

Find the volume of the cylinder with radius 2 cm:

Volume = πr²h

Volume = π(2)²(7) = 28π cm³

Find the volume of the cylinder with the hollow:

63π - 28π = 35π = 110 cm³

Answer: The volume is 110 cm³