Question

There is a path of uniform width 7 m round and outside a circular garden of diameter 210 m. Find the area of the path.

Answer 1

Radius of the circular garden, $r=\frac{210}{2}=105m$
Radius of the region covering the garden and the path, $R=105m+7m=112m$
Area of the region between two concentric circles
with radius of outer circle R, and inner circle r $=\pi (R^2-r^2)$

Hence, the area of the path $=\pi ({112}^2-{105}^2)=\frac{22}{7}(12544-11025)=\frac{33418}{7}=4774m^2$