Ten mathematicians attend a seminar. At the conclusion of the event, every person shakes hands with every other person in the room exactly once. How many total handshakes occur?
45
The number of unique handshakes between 10 individuals is given by combinations: 10 × 9 / 2 = 45.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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