In the given figure PQSR represents a flower be. If OP = 21 m and OR = 14 m, find the area of the flower bed.

Given:

OP = 21 m = r1


OR = 14 m = r2


Let the quadrants made by outer and inner circles be Q1 and Q2, with radius r1 and r2 respectively.


Then, Area of flower bed = Area of Q1 – Area of Q2


Area of Quadrant = πr2


Area of Q1 = πr12


= × × 21 × 21


= m2


Similarly, Area of Q2 = πr22


= × × 14 × 14


= m2


Thus, Area of flower bed = -


= = 192.5 m2


Hence, the area of the flower bed is 192.5 m2.


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