A copper wire when bent in the form of a square encloses an area of 121 cm^2

A copper wire when bent in the form of a square encloses an area of 121 cm2. If the same wire is bent in the form of a circle, it encloses an area equal to

  1. 121 cm2
  2. 144 cm2
  3. 154 cm2
  4. 168 cm2

Answer

The perimeter of square and circle is the same.

4a = 2πr

Given, area of square = a2 = 121 cm2

a = 11 cm

2πr = 4 × 11 cm

r = 7 cm

Area of circle = πr2

= 22/7 × 7 × 7 = 154 cm2

The correct option is C.