Problem:
King Middle School has students. Each student takes classes a day. Each teacher teaches classes. Each class has students and teacher. How many teachers are there at King Middle School?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
There are times a day a student attends a class. Thus there are times a day a teacher teaches a class, so there must be teachers.
If each student took classes and each teacher taught classes, then teachers would be required. But each student takes classes, so teachers are needed.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions