I start with a single bacterium. Every minute, each bacterium splits into two. If the jar is completely full in 60 minutes, at what minute was the jar exactly half full?
59
Since the population doubles every minute, one minute before the jar is completely full (60 minutes), it must be half full.
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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