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Math Help - Truth or lie teller

  1. #1
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    Truth or lie teller

    There are two tribes on an island: truth-tellers and liars. The truth-tellers speak only the truth while liars speak only lies.
    A traveller came across three natives of the island and asked the first native whether he was a truth-teller or a liar. The native replied in a voice so low that the traveller could not hear his the answer.
    So he asked the second native: “What did he say?” to which the second native replied: “He said he was a truth-teller”. At this point the third native, without being asked, stated that the second native lied.
    Was the third native a truth-teller or a liar? Provide a convincing argument to support your claim.
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  2. #2
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    The third guy's full of it.

    Either the first guy is a liar or isn't. Either way, he has to say he isn't. If he tells the truth, he must say he is a truth-teller, and if he is a liar, he cannot say so, so he will say he's a truth-teller. Thus when the second guy reports that the first one said he was a truth-teller, this is true. So the second guy isn't lying. Therefore the third one is.
    Last edited by AlephZero; August 4th 2009 at 09:26 PM. Reason: typos
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  3. #3
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    Much easier: ask anyone "is it raining?" ; get it?
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  4. #4
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    Quote Originally Posted by Wilmer View Post
    Much easier: ask anyone "is it raining?" ; get it?
    Hahahahaha
    Very good question
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