The length and the breadth of a rectangular field are in the ratio 5 :

1.	The length and the breadth of a rectangular field are in the ratio 5 : 4 and its area is 3380 m2. Find the cost of fencing it at the rate of ₹75 per m.
Answer» Ratio in length and breadth = 5 : 4 Area of rectangular field = 3380 m² Let length = 5x and breadth = 4x 5x x 4x = 3380 => 20x²= 3380 x² = 3380/20 = 169 = (13)2 x = 13 Length = 13 x 5 = 65 m Breadth =13 x 4 = 52 m Perimeter = (l + b) = 2 x (65 + 52) m = 2 x 117 = 234 m Rate of fencing = ₹ 75 per m Total cost = 234 x 75 = ₹ 17550

The length and the breadth of a rectangular field are in the ratio 5 : 4 and its area is 3380 m2. Find the cost of fencing it at the rate of ₹75 per m.

Answer»

Ratio in length and breadth = 5 : 4

Area of rectangular field = 3380 m²

Let length = 5x and breadth = 4x

5x x 4x = 3380

=> 20x²= 3380

x² = 3380/20 = 169 = (13)2

x = 13

Length = 13 x 5 = 65 m

Breadth =13 x 4 = 52 m

Perimeter = (l + b) = 2 x (65 + 52) m = 2 x 117 = 234 m

Rate of fencing = ₹ 75 per m

Total cost = 234 x 75 = ₹ 17550