The equation 3s = 21 can be used to find the number of students in each van on a field trip. how many students are in each van

The answer is 7 because if you divide three on both sides you will get s=7.

If we assume that it represents

there are 3 vans that have equl number of students, there are 's' students in each van

total number of studnets is 21

so then s=students per van

3s=21

divide both sides by 3

s=7

7 students per van