Explanation:

- Let's denote the number of female employees as F and the number of male employees as M.

- We know the total number of employees, F + M = 900.

- On the first day, 10% of females were absent, so 90% were present. Therefore, 0.9F females were present.

- On the second day, 8% of males were absent, so 92% were present. Therefore, 0.92M males were present.

- The number of employees present on both days was the same:

- Day 1: 0.9F + M

- Day 2: F + 0.92M

- We need to solve the equation 0.9F + M = F + 0.92M, which simplifies to:

- 0.1F = 0.08M, or

- F = 0.8M

- Substituting F = 0.8M into F + M = 900 leads to:

- 0.8M + M = 900

- 1.8M = 900

- M = 500

- So, the total number of male employees is 500.

Option 4: 500 is correct.