Question

The length of a rectangular field is thrice its breadth . If the area of the field is 7500m sq. ,find the cost of fencing the field at the rate Rs 10 per metre sq.

Answer 1

Let breadth = x m
Given length is 3 times Breadth = 3x m
Area of reactangluar field = l x b = 3x*x = 3x² = 7500

=> x= 50 m
=> Breadth = 50 m
=> length = 3x = 150 m
Perimeter = 2(l+b) = 2(50+150)
= 400 m
Cost of fencing per m = Rs 10
=> Total Cost = 400 x 10 = Rs. 4000