Maths Olympiad Prep

Track / Stage 6 / 6 of 400 #1006 of 1964

Problem 1006

National Olympiad, first round
Combinatorics Difficulty 6.0 Prove it KöMaL problem A · Hungary · 2024

a)a) Two players play a cooperative game. They can discuss a strategy prior to the game, however, they cannot communicate and have no information about the other player during the game. The game master chooses one of the players in each round. The player on turn has to guess the number of the current round. Players keep note of the number of rounds they were chosen, however, they have no information about the other player's rounds. If the player's guess is correct, the players are awarded a point. Player's are not notified whether they've scored or not. The players win the game upon collecting 100 points. Does there exist a strategy with which they can surely win the game in a finite number of rounds?

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