Question

The length of a rectangle is 3 times its breadth. If the perimeter is 84 m , find the length of the rectangle

Answer 1

Let the length be x  and breadth be  y  of the rectangle.

Therefore,    x = 3y

Since,   Perimeter  =  2 ( length + breadth)
               84            = 2  ( x + y )
               84            =  2 ( 3y + y )
               84 / 2       =   4y
               42            =   4y
               y              =   42 / 4
               y              =  10.5 m

Therefore,   x = 3 x 10.5
                   x  = 31.5 m

Answer:- Length of the rectangle is 31.5m

I hope you get it...................