Question

The perimeter of a rectangle becomes __________ times its original perimeter if its length and breadth are doubled.

Answer 1

The perimeter of the rectangle.

The perimeter $\left(P\right)$ of the rectangle is computed from the following formula:

$P=2(l+b)$

Where $l$ is the length and $b$is the breadth of the rectangle.

When length and breadth are doubled. Then, the new perimeter$P\text{'}$ will be,

$$\begin{gathered} P\text{'}=2(2l+2b) \\ P\text{'}=2·2(l+b)\left[\because P=2(l+b)\right] \\ P\text{'}=2P \end{gathered}$$

Hence, the perimeter of a rectangle becomes two times its original perimeter if its length and breadth are doubled.