Q6 of 68 Page 16

A steel wire when bent in the form of square encloses an area of 121cm2. If the same wire is bent in the form of a circle, find the area of the circle.

Area of square = 121 cm2

a2 = 121

a = = 11cm

Perimeter of square = length of wire

4a = 4 ×11 = 44cm

Perimeter of circle = 2πr

2πr = 44

= 7cm

Area of circle = πr2

Area of circle = = 154cm2

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