# Cost of levelling the track at the rate of Rs.10 per sq. metre is:

The outer circumference of a circular race-track is 528 metre. The track is everywhere 14 metre wide. Cost of levelling the track at the rate of Rs.10 per sq. metre is:

- Rs.66760
- Rs.76760
- Rs.77660
- Rs.67760

**Answer: (4) Rs. 67760**

**Explanation:-**

The outer circumference of a circular track = 528 meter

Then, 2 π r = 528

r = 528 x 7/22 x 2

r = 84 meter

The outer radius of the circular track = 84 meters

Then, the total area of circular field = 22 x 84 x 84/7

= 22176 m²

The wide of the circular track = 14 meters

Then, the internal radius of circular field = 84 – 14

= 70 meters

The internal area of the field = 22 x 70 x 70/7

= 15400 m²

Then, the area of the track = 22176 – 15400

= 6776 m²

The cost of the leveling of the track = Rs. 10 /m²

Then, the cost of the leveling track = 6776 x 10

= Rs. 67760

Hence, the answer is (4) Rs. 67760.