Answer: 3 classes
If we removed 5 students from each of the classrooms, we would be able to keep the 18 classes and give them exactly 30 students. However, we would also have the leftover students to put into classrooms.
If there are 18 classrooms with 5 extra students from each, we can use 18*5 to find how many total students we have.
18 * 5 = 90.
If each class size is 30, we need to divide 90 by 30 to find how many classes we need.
90 / 30 = 3 classes
