Question

The length of a rectangle is increased by 60%. By what percent would the width have to be decreased so as to maintain the same area?

• A. 75/2%
• B. 60%
• C. 75%
• D. 120%
• E. None of these

Answer 1

The correct option is A

75/2%

Let original length = `x' and original breadth = `y' Then, original area = xy
New length = $\frac{160x}{100}=\frac{8x}{5}.$
Let new breadth = z
Then, $\frac{8x}{5}\times z=xy=\frac{5y}{8}$ $\therefore$
Decrease in breadth = $\left(\frac{3y}{8}\times \frac{1}{y}\times 100\right)$