How do you solve this algebraic world problem?

Question

In a local basketball league championship, a total of 198 games were played, where each team played exactly 3 games with all the other teams. How many teams participated in this championship?

Answer 1

If there are n teams and a given team played each of the other n-1 teams 3 times, then they would play

3*(n-1) games. Therefore 198 = 3 * (n-1) = 3n - 3 -> 201 = 3n -> n = 67

So there were 67 teams.