Multiple choice general knowledge

If seven people meet each other and each shakes hands only once with each other, how many handshakes will there have been?

  1. 21

  2. 43

  3. 35

  4. 36
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Each handshake involves 2 people, so we need to count unique pairs. For 7 people, the number of handshakes is 7C2 = 7!/(2!×5!) = (7×6)/2 = 21. This is the combination formula for selecting 2 people from 7. Each pair shakes hands exactly once, so 21 unique handshakes occur.

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