A bag contains 3 red marbles and 2 blue marbles. Without looking, what is the minimum number of marbles you must draw to guarantee getting at least one red marble?
3
In the absolute worst-case scenario, you could draw both blue marbles first. Drawing a 3rd marble guarantees it will be red.
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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