# The reason for the grapes, the math enigma of “The World” n°5

It’s the end of the meal and the fruit basket sits in the middle of the table

It’s the end of the meal and the fruit basket sits in the middle of the table. Suddenly, your neighbor at the table grabs a bunch of grapes and meticulously removes nine, which he arranges into a 3 × 3 square.

— I offer you a game, he tells you, of which here are the rules. Each in turn we will take a certain number of these grapes. There is only one constraint: you have to take grapes that are aligned.

— I'm not sure I understand, asks another guest who was listening to the conversation. Can you have just one grape?

- Quite ! A single grape is always aligned with itself. And two grapes are also always aligned: through two points, one and only one line passes, to put it in the manner of Euclid. On the other hand, to take three grapes, they must be on the same line, the same column or the same diagonal.

- I see.

— Whoever takes the last grain wins the game... and the loser does the dishes.

You take a look at the table around you and definitely don't want to spend your evening diving.

— Do you want to start?, your neighbor offers.

How do you answer this question and what game strategy will you employ?

Find the previous puzzles by clicking here

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