Question

The length of a rectangle is thrice its breadth. If the perimeter of the rectangle is $120$ cm, what is the breadth of the rectangle?

Answer 1

Let length of rectangle$=lcm$

breadth of rectangle$=bcm$

Given length is $3$ times its breadth

i.e.$l=3\times b$

Perimeter of the rectangle$=120cm$

i.e.$2\times (l+b)=120$

$2\times (3\times b+b)=120$

$2\times (4\times b)=120$

$8\times b=120$

$b=15cm$