Q20 of 37 Page 13

The cost of fencing a circular field at the rate of Rs. 24 per metre is Rs. 5280. The field is to be ploughed at the rate of Rs. 0.50 per m2. Find the cost of ploughing the field

Total cost of fencing a circular field = Rs 5280


Cost of fencing per meter = Rs 24


So,




= 220m


Here, the total length of the field would be the circumference of the circular field.


∴ Total length = Circumference of circular field


⇒ 220 = 2πr




Now, Area of the field = πr2




= 3850m2


Now,


Cost of ploughing 1m2 of the field = Rs 0.50


Cost of ploughing 3850m2 of the field = Rs 0.50 × 3850


= Rs 1925


Hence, the cost of ploughing the field is Rs 1925


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