Question

The length of a rectangle is $10cm$ and breadth is $7cm$. What will be the area of a rectangle formed by joining $12$ of these rectangles?

• A. $840c{m}^2$
• B. $840cm$
• C. $84c{m}^2$
• D. $440c{m}^2$

Answer 1

The correct option is A $840c{m}^2$

Given:
The length of the rectangle, $l=10cm$
The length of the rectangle, $b=7cm$

Area of a rectangle $\left(A\right)$ is the product of its length and breadth.
$A=lb$
$A=10cm\times 7cm$
$A=70c{m}^2$

Area of a rectangle formed by joining 12 of the rectangles is:
$A^{\prime }=12A$
$A^{\prime }=12\times 70$
$A^{\prime }=840c{m}^2$