The sides of a rectangular field are in the ratio 3: 4 and its area is 7500 m². What is the cost of fencing it at 25 paise per meter?

Rs 87.5

Area of the rectangle = length x breadth 

7500 = 3y x 4y

7500 = 12y²

y² = \(\frac{7500}{12 }\)

y²= 625

y = 25

thus, sides are: 25 x 3 = 75 cm and 25 x 4 = 100 cm

In order to know the cost of fencing, we need to know the perimeter of the field i.e. 2(l + b)

2(l + b) = 2(75 + 100) = 175 x 2 = 350

Cost of fencing = 350 x 0.25 = Rs. 87.5