You have a barrel of oil. Without using any measuring cups, how can you measure out exactly 2 gallons if you only have a 3-gallon jug and a 5-gallon jug?
Fill the 5-gallon jug, pour from it to fill the 3-gallon jug until the 3-gallon jug is full. The remaining water in the 5-gallon jug is 2 gallons.
5 - 3 = 2 gallons left in the larger jug.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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