The average weight of a class of students is 67.5 kg. The weight of the class teacher is 25% more than the average weight of the class. The average weight of the class is less than the class teacher by x%. The value of x is:

Explanation:-

100 ==25% ↑ ==> 125 ==x%↓ ==> 100.
x% = (25 *100) /100 = 20%.
We don't need the actual value to calculate the answer.