Question

A road is $3.5$ m wide surrounding a circular plot whose circumference is $44$ m. Find the cost of paving the road at Rs. $10$ per ${\text{m}}^2$.

Answer 1

Radius of plot$=\frac{44}{2\pi }=\frac{44}{44}\times 7=7$ m.

Area of road$=\pi [{\left(10.5\right)}^2-7^2]=61.25\times \pi$

$=192.42255$ m${}^2$.

$\therefore$Cost Rs. $=1924.22$