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. forty three

  2. twenty one

  3. thirty three

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Each person shakes hands with 6 other people (7-1=6). This would give 7×6=42 handshakes, but each handshake is counted twice (once for each participant). Therefore, the actual number is 42/2=21. This follows the formula n(n-1)/2 for handshake combinations.

Keep practicing — related questions