Question

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

Answer 1

Given,

Area of the circular playground = 22176 m²

And the cost of fencing per metre = ₹50

If the radius of the ground is taken as r.

Then, its area = πr²

πr² = 22176

r² = 22176(7/22) = 7056

Taking square root on both sides, we have

r = 84 m

We know that, fencing is done only on the circumference of the ground

Circumference of the ground = 2πr = 2(22/7)84 = 528 m

So, the cost of fencing 528 m = ₹50 x 528 = ₹26400

Therefore, the cost of fencing the ground is ₹26400.