Question

The breadth of a rectangular hall is $\frac{3}{4}$ its length. If the area of the hall is $300$ square metres, what is the difference between the length and breadth of the hall?

• A. $15m$
• B. $5m$
• C. $4m$
• D. $3m$

Answer 1

The correct option is B $5m$

Let the length of the hall be $Lm.$
Then, breadth $=\frac{3}{4}L$
Area $=L\times \frac{3}{4}L=300$
$\Rightarrow L^2=400\Rightarrow L=20m$
$\therefore$ Breadth $=\frac{3}{4}\times 20m=15m$
Hence, reqd. difference $=(20-15)m=5m.$