Given:
Number of boys = 5
Number of girls = 4
To find:
The number of ways in which 5 boys and 4 girls be arranged on a bench if there are no restrictions.
Solution:
We have, 5 boys and 4 girls.
Total number of boys and girls:

If there are no restrictions, then the total number of ways to arrange 9 persons is:




Therefore, the total number of ways to arrange 5 boys and 4 girls is 9! or 362880.