A magical clock loses 3 minutes every hour. If I set it to the correct time right now, exactly how many hours will pass before the clock shows the exact right time again?
240 hours
A clock must lose a full 12 hours (720 minutes) to look correct again. At a rate of 3 minutes lost per hour, you divide 720 by 3, which equals 240 hours.
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: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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