Question

The area of a circular playground is $22176m^2$. Find the cost of fencing at the rate of $Rs.50$ per m.

Answer 1

Area of circular playground $=22176c{m}^2$

$\Rightarrow \pi r^2=22176\Rightarrow r^2=\frac{22176\times 7}{22}=7056\Rightarrow r=\sqrt{7056}=84m$

Perimeter of playground $=2\pi r=2\times \frac{22}{7}\times 84=528m$
Cost of fencing $=Rs(50\times 528)=Rs26400$