In a school club, 20 students play soccer, 15 play chess, and 5 play both. How many students are in the club in total?
30
Using the Principle of Inclusion-Exclusion: Total = Soccer + Chess - Both. Total = 20 + 15 - 5 = 30.
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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