Question

A park is in the shape of a circle and a person walking on the boundary covers a distance of 440 m on one round. find the diameter of the park and also the cost of covering it with gravel at the rate of ₹225 per m ²​

Answer 1

Answer:

A park is in the shape of a circle and a person walking on the boundary covers a distance of 440 m on one round.

The diameter of the circle is 140m.

The cost of covering it with gravel at the rate of ₹225 per m ²​ is ₹34,65,000.

Step-by-step explanation:

If a park is in the shape of a circle and a person walking on the boundary covers a distance of 440 m on one round.

Then circumference = 440m

Step 1: Find the diameter

circumference =πd

22/7  × d = 440

d = 440  ×  7/22

d = 20  ×  7

d = 140 m

So, the diameter of the circle is 140m.

Step 2: Find area of circle and cost of covering it with gravel

r = d/2 = 140/2 = 70 m

Area of circle = $\pi r^2$

$=\frac{22}{7} \times 70^2\\=\frac{22}{7} \times 70 \times 70 \\=22 \times 10 \times 70 \\= 15400 m^2$

The cost of covering it with gravel at the rate of ₹225 per m ²​

= ₹225 × 15400

= ₹34,65,000

Hence The cost of covering it with gravel at the rate of ₹225 per m ²​ is ₹34,65,000.