Question

A circular pond is of diameter 17.5 m. It is surrounded by a 2 m wide path. Find the cost of constructing the path at the rate of Rs. 25 per square metre (Use $\pi$ = 3.14).

Answer 1

Given radius$\left(r\right)=\frac{17.5}{2}m$ and width of the path$\left(w\right)=2m$

Area of path$=\pi (R^2-r^2)$

$R=r+\omega =\frac{17.5}{2}+2=10.75m$

$\therefore Area=3.14({10.75}^2-{8.75}^2)=122.46m^2$

Cost of construction = Rs. $(122.46\times 25)$ = Rs. $3061.5$