Sum Up to 15

Tango and Cash are playing the following game: Each of them chooses a number between 1 and 9 without replacement. The first one to get 3 numbers that sum up to 15 wins. Does any of them have a winning strategy?

Place the numbers from 1 to 9 in a 3×3 grid so that they form a magic square. Now the game comes down to a standard TIC-TAC-TOE and it is well-known that it always leads to a draw when both players use optimal strategies.

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Responses

  1. Yes, I read about sum to 15 in an audiobook by Scott E Page. He does say who invented it, but I forgot. The strategy is a noughts and crosses type grid. I was looking for more info.