The area of a circular cricket ground is 24.64 hectares. Find the cost of making rope boundary at the rate of Rs. 5.40 per metre.
1 hectare = 10,000 sq. m
Let radius of ground = $$r$$ m
=> Area of ground = 24.64 hectares = 246400 sq. m
=> $$\pi r^2=246400$$
=> $$\frac{22}{7}\times r^2=246400$$
=> $$r^2=246400\times\frac{7}{22}=78400$$
=> $$r=\sqrt{78400}=280$$ m
Now, circumference = quantity of rope required = $$2\pi r$$
= $$2\times\frac{22}{7}\times280=1760$$ m
$$\therefore$$ Total cost = $$1760\times5.40=Rs.$$ $$9,504$$
=> Ans - (B)
Create a FREE account and get: