The area of a circular playground is 22176 m2. Find the cost of fencing this ground at the rate of `50 per m.

Area of the circular playground = 22176 m2 (Given)


Let r be the radius of the circle.


∴ πr2 = 22176


⇒ (22/7)r2 = 22176


⇒ r2 = 22176 × (22/7)


⇒ r2 = 7056


⇒ r = 84


∴ Radius of the circular playground = 84 m


Now, circumference of the circle = 2πr


= 2×(22/7)×84


= 528 m


Cost of fencing 1 meter of ground = Rs 50


∴ Cost of fencing the total ground = Rs 528 × 50 = Rs 26,400


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