The radius of a circular card board is 20 cm. A strip of width 4 cm is removed all along its border. The percenrage of the area of the strip removed is _______.

From a circular aluminium sheet of radius 14 cm, a sector of angle 45^(@) is removed. Find the percentage of the area of the sector removed.

From a square sheet of side 8 cm , a piece of a paper width 2 cm is removed along the border. Then find the area of the removed piece of paper.

The radius of a semi-circular protactor is 14 cm. Find its perimeter and area.

A sheet of paper measures 35 cm by 25 cm . A strip of 5 cm width is cut from it , all around Find the area of the remaining sheet and also the area of the cut - out strip.

From a circular sheet of radius 4 cm, a circle of radius 3 cm is removed. Find the area of the remaining sheet. (Takepi = 3.14)

Height of a right circular cylinder is 20 cm.If the radius is its base 14 cm, then what will be the curved surface area of the cylinder?

The outer radius of a circular ring is 21 cm.and its area is 26cm^2 .Find its inner radius.

The radius of a right circular cone is 3 cm and its height is 4 cm. The total surface area of the cone is