The answer is - only one. The last one should say the color of the hat the sage before him not his. If he is lucky and has the hat of the same color than nobody would be killed.

>Hi Alex,
>
>Both solutions are not entirely correct. The only word, that each sage can say is "Black" or "White". Therefore he can not give clues, like my Hat is the same color as in front of me...
>
>BTW, the solution is very simple, I'm amazed, that I didn't get it yet. I solved it in a train in 1 minute...
>
>>>Puzzle 1:
>>>
>>>100 sages stay in a row. Each sage wears a hat, which might be either white or black. Each sage can see everyone, who stays before him, e.g. the last one sees 99 sages, 99th sees 98 and so on...
>>>
>>>They have been told, that each sage, who identifies his hat's color incorrectly, would be killed. They have a minute to find a best strategy (discuss this situation among them). They should pronounce loudly the color of his hat starting from the last one to the first one (each one hears, what the other say). Now the question: How many sages can survive and what would be their strategy?
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