Answer: 120
=======================================================
Step-by-step explanation:
Draw a circle and split it into 4 equal pieces.
We'll split the 160 students into four equal groups
160/4 = 40
Write the number 40 in each slice. Shade 3 of those slices to represent 3*40 = 120 students went to the pep rally (the remaining 40 did not go).