Three statements about the day, exactly one true
Three people speak. Exactly one of them is telling the truth.
- Alice: "Today is Tuesday."
- Bob: "Tomorrow is Thursday."
- Carol: "Yesterday was Tuesday."
What day is it? Show that only one day is consistent with exactly one true statement, and say which two statements end up agreeing with each other.
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Suppose each speaker in turn is the truthful one, work out the day, and check that the other two statements come out false.
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