Sponsor Area

Areas Related To Circles

Question
CBSEENMA10009822

In fig., OABC is a square of side 7 cm. If OAPC is a quadrant of a circle with centre O, then find the area of the shaded region.  Use π = 227

                               

Solution

                           

Given: OABC is a square  of side 7 cm

i.e. OA = AB = BC = OC = 7 cm

 Area of square OABC = ( side )2 = 72 = 49 sq. cm.

 

Given, OAPC is a quadrant of a circle with centre O.

 Radius of the sector = OA = OC = 7 cm.

Sector angle = 900

 Area of quadrant OAPC = 9003600 x πr2                                                  = 14 x 227 x 7 x 7                                                 = 772 sq.cm.                                                                                                = 38.5  sq.cm. Area of shaded portion = Area of square OABC - Area of quadrant OAPC                                               = (49 - 38.5) sq.cm.                                               = 10.5 sq.cm.