The length of rectangle is thrice its breadth and its perimeter is 48cm. Find length and breadth of rectangle.

Let the breadth of rectangle = b
length of rectangle = 3b
Perimeter of rectangle = 2 × (3b + b)
48 = 2 × (3b + b)
48/2=4b
24 = 4b
24/4=b
⇒ 6 = b ⇒ breadth = 6cm
length = 3b = 3 × b = 18cm