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# System prepended metadata

title: The Prisoner Hat Puzzle with three colours

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# The Prisoner Hat Puzzle with three colours


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**Activity:** Can you solve the prisoner hat puzzle if there are three possible colours of hats?

Hint: Revisit your solution for two colours. If you formulated it in terms of even and odd, rewrite your solution in terms of addition modulo 2. Then generalise to addition modulo 3.