Rohan's salary was cut by x%, and later the reduced salary was raised by x%. He now earns 4% less than his original salary. What is x?

Explanation

1. 01

   Net change for −x% then +x% is $-\frac{x^2}{100}\%$.

2. 02

   $\frac{x^2}{100} = 4$, so $x^2 = 400$ and $x = 20$.

3. 03

   Check: 100 → 80 → 96, which is 4% less.