Question

the side of a rectangle are in ratio 5:4.if primetre is 144 then its length is

Answer 1

Let its length and breadth be 5x and 4x
Then, perimeter =2(5x+4x)
=2*9x=18x
But given perimeter=144
So, 18x=144
x=144/18
x=8
Hense length =5x=5*8=40
Hope this will help you

Answer 2

Here is your solution

Given :-
The sides of a rectangle are in the ratio of 5:4

Lenght = 5x
Breadth =4x


Perimeter of rectangle = 2 (l+b)
144=>2 (5x+4x)
144=>2 ×9x
72=>9x
8=>x

Length = 5x = 5×8=40unit

Hope it helps you