Adam goes to a small school, which teaches 80 students in three classes. 40% of the students are in class A, and class B has 21 students fewer than class A. The rest are in class C. How many students are in this class? Let's answer step by step:
In class A, there are 40 / 100 * 80 = 32 students. In class B, the number of students is less by 21, which means class B has 32 - 21 = 11 students. That means 80 - 32 - 11 = 37 students are in class C. The answer: 37.