Radius (r_{1}) of larger circle = 7 cm

Radius (r_{2}) of smaller circle =7/2 cm

Area of smaller circle = πr_{1}^{2}

=22/7 x 7/2 x 7/2

=77/2 cm^{2}

Area of semi-circle AECFB of larger circle = 1/2 π r_{2}^{2}

= 1/2 x 22/7 x 7 x 7

= 77 cm^{2}

Area of ΔABC = 1/2 x AB x OC

= 1/2 x 14 x 7

=49 cm^{2}

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 cm^{2}