Question

The sides of a rectangular park are in the ratio 4:3 .If its area is 1728 meter square find :
1. perimeter
2. cost of fencing it at the rate of rupees 40 per meter

Answer 1

Answer:

Step-by-step explanation:

Let the side be x.

Area = l*b

=> 1728 = 4x*3x

=> 1728 = 12x²

=> 1728/12 = x²

=> 144 = x²

=> 12 = x

Sides: 4x = 4*12 = 48m

3x = 3*12 = 36m

Perimeter = 2(l+b)

=> 2(48+36)

=> 2(84)

=> 168m

Cost of fencing at Rs.40 per metre.

=> 168*40

=> Rs.6720

Answer 2

Let's the side be = x

then,

first side = 4x

second side= 3x

given area= 1728m^2

:area=first side × second side

4x × 3x = 1728 = x^2 = 1728/12

x^2 = 144

x= 12

first side=4×12=48

second side=3×12=36

perimeter=2(48+36)=2(84)=168m. And

2. cost=168/40=4.2 Ans.