Answer 1

Let the length and breadth of the rectangle be 3x cm and x cm, respectively.
Perimeter of the rectangle = 36 cm
∴ 2(Length + Breadth) = 36 cm
⇒ 2(3x + x) = 36
⇒ 2 × 4x = 36
⇒ 8x = 36
⇒ x = 4.5
∴ Length of the rectangle = 3x = 3 × 4.5 = 13.5 cm
Breadth of the rectangle = x = 4.5 cm
Thus, the length and breadth of the rectangle is 13.5 cm and 4.5 cm, respectively.