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25 lines
784 B
25 lines
784 B
2 years ago
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Exercise 4.42: Solve the following “Liars”
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puzzle (from Phillips 1934):
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Five schoolgirls sat for an examination. Their parents—so they
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thought—showed an undue degree of interest in the result. They therefore
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agreed that, in writing home about the examination, each girl should make one
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true statement and one untrue one. The following are the relevant passages
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from their letters:
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Betty: “Kitty was second in the examination. I was only third.”
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Ethel: “You’ll be glad to hear that I was on top. Joan was second.”
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Joan: “I was third, and poor old Ethel was bottom.”
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Kitty: “I came out second. Mary was only fourth.”
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Mary: “I was fourth. Top place was taken by Betty.”
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What in fact was the order in which the five girls were placed?
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