Question

A 3m wide road around a circular park whose circumference is132m.Find the cost of fencing the outer boundary of the road at the rate of 10 rupees per m .

Answer 1

$2 \times \pi \times x$
Let x be radius of inner circle. Then given circumference=132m
Equate with formula to get x =10. 5 m and add 3m to get outer radius and put in formulae
$2 \times \pi \times r$
to get circumference 88.4m and multiply with 10rs to get cost of boundary 844rs