Radius (r1) of larger circle = 7 cm
Radius (r2) of smaller circle =7/2 cm
Area of smaller circle = πr12
=22/7 x 7/2 x 7/2
=77/2 cm2
Area of semi-circle AECFB of larger circle = 1/2 π r22
= 1/2 x 22/7 x 7 x 7
= 77 cm2
Area of ΔABC = 1/2 x AB x OC
= 1/2 x 14 x 7
=49 cm2
Area of the shaded region = Area of smaller circle + Area of semi-circle AECFB − Area of ΔABC
= 77/2 + 77-49
=28 + 77/2 = 28 + 38.5
=66.5 cm2