Four of the 16 students in Ms. Salas’s class after school are serving detention. The rest of the students are there for tutoring. Using the diagram below, determine the percent of the students in Ms. Salas’s classroom after school who were there for detention. Choices:

A: 16%
B: 25%
C: 40%
D: 60%

The answer is b because 4/16 students are in detention. 25% means 1/4. if u break the group of 16 into four groups, there will be four students in each group (4+4+4+4=16) since four students are in detention, one full group will be in detention so 1/4. this is the best i can explain this but if you would like the mathematical proof work it is:
4 divided by 16 = 0.25 which turned into a percent is 25%