A barrel of water weighs 60 pounds. What must you add to the barrel so that it weighs 40 pounds?
A hole
Adding a hole lets water leak out, reducing the total weight of the barrel.
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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