Five players enter a round-robin chess tournament where every player plays every other player exactly once. How many total matches will be played in the tournament?
10 matches
Using the combination formula n(n - 1) / 2 for 5 players gives (5 × 4) / 2 = 10 unique matches.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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