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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

Excel in math and science

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It's hard to learn from lectures and videos

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Our wiki is made for math and science

Master advanced concepts through explanations,
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including olympiad champions, researchers, and professionals.

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View solutions

by Peter Macgregor

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