Question

A road which is 7 m wide surrounds a circular park whose circumference is 352 m. Find the area of the road.

Answer 1

Circumference of circular park = 352 m

$\Rightarrow 2\pi r=352$ where $r$ is the radius of the park

$\Rightarrow 2\times \frac{22}{7}\times r=352$

$\Rightarrow r=56m$

Now, outer radius $=56m+7m=63m$

Area of the road $=\pi \times {63}^2-\pi \times {56}^2=\pi ({63}^2-{56}^2)=\frac{22}{7}\times (63+56)\times (63-56)$

$=\frac{22}{7}\times 119\times 7=2618m^2$