Question

A gardener wants to fence a circular garden of diameter $21m.$ Find the length of the rope he needs to purchase, if he makes $2$ rounds of fence. Also find the costs of the rope, if it cost $Rs.4$ per meter. (Take $\pi =\frac{22}{7}$)

Answer 1

Given: Diameter of the circular fence, $d=21m$

Radius of the circular fence, $r=\frac{21}{2}m$

Circumference of the circular garden $=2\pi r=2\times \frac{22}{7}\times \frac{21}{2}=66m$

Length of the rope required to fence $1$ time $=$ Circumference of the circular garden

Length of rope required for fencing $2$ times $=2\times 66m=132m$

Cost of $1m$ rope $=Rs.4$

Cost of $132m$ rope $=4\times 132=Rs.528$