Question

the diameter of thee circles In the figure are 21cm ,14cm and 7cm what is the area of the shaded region

Answer 1

Area of all three circles= pie× radius^2
1st circle= 22/7 × 21/2cm ×21/2cm
=346.5cm^2
Area of 2nd circle= 22/7 × 14/2cm × 14/2cm
= 154cm^2
Area of 3rd circle= 22/7 × 7/2cm×7/2 cm
=38.5cm^2
Area of shaded region= 346.5cm^2-( 154+38.5)cm^2
= 346.5cm^2 - 192.5cm^2
= 154cm^2
Hope it helps

Answer 2

Area of bid circle=πr2
22/7×10.5×10.5(radius=21/2=10.5)
=346.5cm2
Similarly,area of both small circle=154 and 38.5 sum of both small circle area's will 192.5
Area of shaded portion= 346.5-192.5
Will give 154cm