Question

if the diameter of a circular pond is 84 metre,find the cost of fencing around it with four rounds at Rs 12 per metre ​

Answer 1

Solution

Given :-

• Diameter of a circular pond = 84 m
• coat of fencing around the circle = 12 rupees per m

Find :-

• Total cost of fencing

Explanation

Formula

$\dag\boxed{\underline{\tt{\red{\:circumference_{cycle}\:=\:2\pi r}}}}$

⁰990

Where,

• r = Radius = 84/2 = 42

==> circumference of circle = 2 × 22/7 × 42

==> circumference of circle = 2 × 22 × 6

==> circumference of circle = 44 × 6

==> circumference of circle = 264 m

Now , calculate Total cost of fencing.

cost of fencing of 1 m circle = ₹ 12

cost of fencing of 264 m circle = 264 × 12

cost of fencing of 264 m circle = ₹3168

Hence

• Total cost will. be = ₹3168

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Answer 2

Given:-

Diameter of circular pond is 84 metres.

Cost of fencing around the pond is 12 rupees per metre.

To Find:-

Cost of fencing the circular pond

Solution:-

Formula to find circumference of circle:-

$\huge \boxed{ \red{2\pi r}}$

$\bigstar$Radius = 84/2

= 42 m

Now, the circumference of circle:-

$2 \times \pi \times radius \\ \\ 2 \times \frac{22}{ \cancel7} \times \cancel{42} \\ \\ 2 \times 22 \times 6 \\ \\ 44 \times 6 \\ \\ = {264 \: metre \: }^{2}$

Now, total cost of fencing:-

$\bigstar$Cost of fencing per metre square = 12 rupees

$\bigstar$Cost of fencing 264 metre square = 12×264 = 3168 rupees

$\bigstar$Cost of fencing with four rounds = 3168×4 = 12,672

Hence, the cost of fencing around the circular pond with four rounds is 12,672 rupees.