# Question: A round robin tournament of n contestants is a tournament in

A round-robin tournament of n contestants is a tournament in which each of the

pairs of contestants play each other exactly once, with the outcome of any play being that one of the contestants wins and the other loses. For a fixed integer k, k < n, a question of interest is whether it is possible that the tournament outcome is such that, for every set of k players, there is a player who beat each member of that set. Show that if

then such an outcome is possible.

Suppose that the results of the games are independent and that each game is equally likely to be won by either contestant. Number the

sets of k contestants, and let Bi denote the event that no contestant beat all of the k players in the ith set. Then use Boole’s inequality to bound

pairs of contestants play each other exactly once, with the outcome of any play being that one of the contestants wins and the other loses. For a fixed integer k, k < n, a question of interest is whether it is possible that the tournament outcome is such that, for every set of k players, there is a player who beat each member of that set. Show that if

then such an outcome is possible.

Suppose that the results of the games are independent and that each game is equally likely to be won by either contestant. Number the

sets of k contestants, and let Bi denote the event that no contestant beat all of the k players in the ith set. Then use Boole’s inequality to bound

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