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 10%

B 10.08%

C 20%

D 28%

Solution

Correct Answer: Option D

Suppose ,

a number is decreased by =x% and then again decreased by length =y% Then,

net change ={−x−y+(xy/100)} % = 28%