Answer:
4.8 sheets of paper
Explanation:
You just need to divide 120 by 25 students. The reason for that is because you need to find out how much *each* student has. 
120/25 = 4.8
As a fraction 
Mixed = 4 4/5
Improper = 24/5
The unit rate is any of these answers! Don't forget your units :)