Question

Find the area of the shaded region in the given figure if radii of the two concentric circles with centre O are 7cm and 14 cm respectively and ∠AOC = 40°.

Answer 1

Given: Radius of the small circle, OB = 7cm

Radius of second circle, OA = 14cm

and ∠AOC = 40°

= 68.4 cm²

Area of the shaded region = Area of sector OAC – Area of sector OBD

= 68.4 – 17.1

= 51.3 cm²