A farmer needs to measure out exactly 4 liters of water using only an unmarked 3-liter jug and an unmarked 5-liter jug. What is the minimum number of steps to get 4 liters in the 5-liter jug?
6 steps
1) Fill the 5L jug. 2) Pour 5L into the 3L jug (2L remains in 5L jug). 3) Empty the 3L jug. 4) Pour the 2L from the 5L jug into the 3L jug. 5) Fill the 5L jug completely. 6) Pour water from the 5L jug to top off the 3L jug (which needs 1L). Exactly 4 liters remain in the 5L jug.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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