Two numbers X and Y are respectively 20% and 28% less than a third number Z. By what percentage is the number Y less than that of the number X?
Q1. Two numbers X and Y are respectively 20% and 28% less than a third number Z. By what percentage is the number Y less than that of the number X?
Answer: 10%
Explanation: X = 0.8Z and Y = 0.72Z; Y is less than X by (0.8 − 0.72)/0.8 × 100 = 0.08/0.8 × 100 = 10%.