The cost of fencing a circular field at the rate of Rs. 25 per meter is Rs. 5500. The field is to be ploughed at the rate of 50 paise per m^{2}. Find the cost of ploughing the field. [Take π = 22/7]

Given:

Rate of fencing a circular field = Rs. 25/m

Cost of fencing a circular field = Rs. 5500

Rate of ploughing the field = 50p/m^{2} = Rs. 0.5/m^{2}

Let the radius of circular field be ‘r’ and the length of the field fenced be ‘x’ m.

Then, 25 × x = 5500

x = = 220 m

∵ Circumference of circular field = 2πr

∴ 220 = 2πr

220 = 2 × × r

r =

r = 35 m

Area of the circular field = πr^{2}

= × 35 × 35

= 22 × 5 × 35

= 3850m^{2}

Now, cost of ploughing the field = Rate of ploughing the field × Area of the field = 0.5 × 3850

= Rs. 1925

__Hence, the cost of Ploughing the field is Rs. 1925.__

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