Eight people at a meeting each shake hands once with every other person. How many handshakes take place?
Answer and explanation
Correct answer: A. 28
- Step 1: Each person shakes 7 hands, giving 8 × 7 = 56 hand-ends. Step 2. Each handshake has two ends, so halve: 56 ÷ 2 = 28. Answer: 28. Why not the others: 56: This counts each handshake twice, 8 × 7. 64: This has each person shake hands with all eight people, including themselves. 36: This adds 1 + 2 + ... + 8, which counts one extra person.
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