Answer is there are 24 males and 9 females in class for a total of 33
Step by step
We know there are 33 students
We know there are n + 15 males
We know there are n females
We are looking for how many females are in the class
n + (n + 15)= 33
2n + 15 = 33
2n + 15 -15 = 33 -15
2n = 18
n = 9
Check your work
15 + 9 + 9 = 33
33 = 33
Problem solved!