Question

the cost of fencing a square field at Rupees 1.60 per metre is rupees 3200 find the cost of reaping in the field at Rupees 1.20 per metre 100 square metre

Answer 1

First we can take out the perimeter of the square = 3200/1.60 = 2000 meters 
Then the side of the square will be 2000/4 = 500m
Then take out its area = 500 * 500 $m^{2}$ =250000 $m^{2}$
The cost of reaping is Rs 1.20 per 100$m^{2}$ 
Total amount = Rs. 250000/100 * 1.20 = Rs. 3000
the cost of reaping in the field at Rupees 1.20 per metre 100 square metre is Rs.3000