Question

the diameter of a circular park is 24m. A 3m wide path runs around it from inside . find the cost of paving the path at ₹25 per square meter.

Answer 1

Since the Diameter= 24m. The Radius will be = D/2= 24/2 = 12m.

It is given that a 3m wide path runs around it from 'inside'. Therefore, the Radius of the bigger circle will be 12-3= 9m

Area of bigger circle= pi r²
                                = 22/7 * 12 * 12 = 452.57m²

Area of smaller circle = pi r²
                                   = 22/7 * 9 * 9 = 254.57m²

So the area of path= Area of bigger circle- Area of smaller circle
                               = 452.57- 254.57
                               = 198 m²

The total cost= 198* 25= Rs. 4950

Answer 2

Answer:

₹4950

Step-by-step explanation:

Let the diameter of the

circular park ( D ) = 24 m

Radius of the park ( R ) = D/2

R = 24 /2 = 12 m

If the width of the path inside the

park ( w ) = 3m

Radius of the inside circle (r ) = R - w

r = 12 - 3 = 9 m

Area of the path ( A ) = πR² - πr²

A = π(R + r ) (R - r )

= π ( R + r ) w

= ( 22 /7 ) ( 12 + 9 ) ( 3 )

= 22 × 3 × 3

A = 198m²

Cost of the paving the per square

meter = Rs 25

Cost of paving total area of the path

=25 × 198

= Rs4950

I hope this helps you.

:)