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Handshakes

Discrete Mathematics Level 1

5 people became friends at a Summer Camp. On the last day, they shook each other's hands to say farewell. How many handshakes were there?

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,
examples, and problems from the community.

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including olympiad champions, researchers, and professionals.

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by Arron Kau

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