RU-ALLRUSSIAN 2015 Problem 113
teams participate in a volleyball tournament. Every team has played every other team exactly once (there are no ties in volleyball). Turns out that in any set of teams, there is one which has lost to no more than of the remaining teams. Prove that in the entire tournament, there is a team that has lost to no more than of the remaining teams.
Dataset text AI-MO AoPS. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.
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