Ten executives attend a conference. If every executive shakes hands with every other executive exactly once, what is the total number of handshakes?
45 handshakes
The number of handshakes among N people is given by N × (N - 1) / 2. For 10 people: 10 × 9 / 2 = 45.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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