A towel, when bleached, was found to have lost 20% of its length and 10% of its breadth. The percentage of decrease in area is:

A towel, when bleached, was found to have lost 20% of its length and 10% of its breadth. The percentage of decrease in area is:

A 18%

B 28%

C 38%

D 48%

Solution

Correct Answer: Option B

Let original length = x and original breadth = y.

Decrease in area = xy - \(\left(\frac{80}{100}x\times\frac{90}{100}y\right)\)

= (7/25)xy

Decrease % = (7/25)xy * (1/xy) * 100

= 28%