Sponsor Area

Areas Related To Circles

Question
CBSEENMA10009741

In Fig., AB and CD are two diameters of a circle with centre O, which are perpendicular to each other. OB is the diameter of the smaller circle. If OA = 7 cm, find the area of the shaded region.   Use π = 227

               

Solution

AB and CDare the diameters of a circle with centre O. OA = OB = OC =7 cm ( Radius of the circle)Area of the shaded region = = Area of the circle with diameter OB + ( Area of the semi-circle ACDA - Areaof ACD )=π 722 +  12 x π x 72 - 12 x CD x OA= 227 x 494 + 12 x 227 x 49 - 12 x 14 x 7= 772 + 77- 49= 66.5 cm2