Question

the length and breadth of the rectangular field are in the ratio 3:2.if the area of the field is 3456m2; find the cost of fencing it at rs 80 per m​

Answer 1

let the ratio as 3x and 2x

so area would be

$3x × 2x = 3456m^2$

$6x^2 = 3456m^2$

$x^2 = \frac{3456m^2}{6}$

$x^2 = 576m^2$

square root both side

$\sqrt{x^2} = \sqrt{576m^2}$

$x = 24$

so the sides would be

3×24 = 72

2×24 = 48

so perimeter would be

=2×(72+48)
=2×120
=240m

so the cost of fencing would be

240×80 = 19200

Answer 2

Let the length and breadth be 3x and 2x

We know that the area of rectangle is2(l+b)

So,3456=2(2x+3x)

=>10x=3456

=>x=3456÷10

=>x=345.6m

So,1m=RS 80

Therefore,345.6m =rs 80×345.6

=RS 27648