Question

A 3 m wide road runs around a circular park whose circumference is 132 m. Find the cost of fencing the outer boundary of the road at the rate of $10 per m.

Answer 1

The road around the park = 3 m wide,

and the circumference of the park = 132 m,

We have to find the cost of fencing

the outer boundary,

the rate = $10 per m

Step-by-step explanation:

As we know that the circumference

of a circle = 2 × 22÷7 × radius

2 × 22÷7 × radius = 132 m,

44 × radius = 132 m × 7,

44 × radius = 924 m,

radius = 924 ÷ 44 m

So, radius = 21 m ( smaller circle )

radius = 21 m + 3 m ( larger circle )

= 24 m

Usually, we fence on the borders means it's

the circumference of the larger circle

= 2 × 22÷7 × radius

= 44÷7 × 24 m

= 1056÷7 m

= 150.85 m

cost of fencing = $ 10/m

total cost = 150.85 × $ 10

= $ 1508.57

Thank you friends.......