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Tournament Of Towns
1997 Tournament Of Towns
(531) 3
(531) 3
Part of
1997 Tournament Of Towns
Problems
(1)
TOT 531 1997 Spring J A3 - 2n players in chess tournament,
Source:
9/11/2024
In a chess tournament, each of
2
n
2n
2
n
players plays every other player once in each of two rounds. A win is worth
1
1
1
point, a draw is worth
1
2
\frac12
2
1
ā
point and a loss is worth nothing. Prove that if for every player, the total score in the first round differs from that in the second round by at least n points, then this difference is exactly n points for every player. (B Frenkin)
combinatorics