Six people at a meeting each shake hands once with every other person. How many handshakes take place?
Answer and explanation
Correct answer: A. 15
- Step 1: Count pairs: C(6,2) = 6 x 5 / 2. Step 2. That gives 15. Answer: 15. Why not the others: 30 counts each handshake twice, and 36 includes shaking one's own hand.
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