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Exercise 1.4
A round-robin tournament is being held with n tennis players; this means that every player will play against every other player exactly once.
- (a)
- How many possible outcomes are there for the tournament (the outcome lists out who won and who lost for each game)?
- (b)
- How many games are played in total?
Answers
- (a)
- There are
matches.
For a given match, there are two outcomes. Each match has two possible outcomes. We can use the multiplication rule to count the total possible outcomes.
- (b)
- Since every player plays every other player exactly once, the number of
games are the number of ways to pair up to
people.