Question

The cost of fencing a circular field at the rate of RS. $24$ per metre is Rs. $5280$. Calculate
(i) the radius of the field
(ii) the cost of ploughing the field at the rate of Rs. $2$ per $m^2$

Answer 1

Cost of fencing at 24/m= $5280$

perimeter of fence $=\frac{5280}{24}$

$=2\pi r=220$

$r=\frac{220}{2\pi }$

$r=\frac{220}{2\times \frac{22}{7}}=\frac{220\times 7}{2\times 22}=5\times 7$

$r=35$

(i) The radius of field $=35$

(ii) Cost of ploughing the field at the rate of 2/$m^2$

$=\frac{22}{7}\times 35\times 35\times 2$

$=22\times 5\times 35\times 2$

$=220\times 35$

$=7700$