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An Old Chestnut

Discrete Mathematics Level 3

At a meeting with a finite number of attendees, which of the following statements must be true?

An odd number of people shook hands an odd number of times. An even number of people shook hands an even number of times An odd number of people shook hands an even number of times. An even number of people shook hands an odd number of times

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by Peter Macgregor

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