Q. 24.2( 173 Votes )

# Find the area of the shaded region in Fig. 12.20, if radii of the two concentric circles with centre O are 7 cm and 14 cm respectively and ∠ AOC = 40°.

Answer :

Area of the shaded region = Area of Bigger sector – Area of Smaller Sector

If r_{2} and r_{1} are the two radii of Bigger and Smaller circles respectively, then:

Area of bigger sector = 40/360 πr_{2}^{2}

Area of smaller sector = 40/360 πr_{1}^{2}

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