Question

If the length and breadth of a rectangle are doubled , then its perimeter becomes:

• A. triple
• B. double
• C. half
• D. four times

Answer 1

The correct option is B

double

Finding the change in perimeter:

Let the length and breadth of the rectangle be $l$ and $b$respectively.

Therefore, the Perimeter of rectangle $=2\times \left(l+b\right)$……..$\left(i\right)$

According to question, if length and breadth are doubled

Then length $=2l$ and breadth $=2b$

Thus perimeter $=2\times \left(2l+2b\right)=4\times \left(l+b\right)$………….$\left(ii\right)$

From $\left(i\right)$ and $\left(ii\right)$, we can say that perimeter becomes double.

Hence, option(b) is the correct option.