Question

A gardener wants to fence a circular garden of diameter 21m. Find the length of the wire he needs to purchase and cost of it at the rate of Rs 4 per metre

Answer 1

Step-by-step explanation:

So D =21

r=21/2

Cost rupee 4

2πr=2×22/7×21/2

Circumference=66

For twice=132

Cost=132×4=528

Answer 2

Answer:

$\fbox \pink{diameter} = 21m \\ \\ \fbox \purple{radius} = \frac{21}{2}m \\ \\ \fbox \red{circumference} = 2\pi \: r \\ \\ 2 \times \frac{22}{7} \times \frac{21}{2} = \frac{22}{7} \times 21 \\ \\ 22 \times 3 = 66m \\ \\ \fbox \green{length \: of \: rope \: required} = 2 \times 66 = 132m \\ \\ \fbox \blue{cost} = 1m \: rope = 4 \\ \\ 132m \: rope = 4 \times 132 = 528$