A traveler needs to cross a river with a fox, a goose, and a bag of grain. The boat can only hold the traveler and one item at a time. Left alone, the fox will eat the goose, or the goose will eat the grain. How does the traveler get everything across safely?
Take the goose across first. Return alone, take the fox across, and bring the goose back. Leave the goose and take the grain across. Return alone, and finally bring the goose across.
The goose cannot be left alone with the fox or the grain. Taking the goose first leaves the fox and grain safely together. Swapping the goose back on the second return trip keeps all pairs separated when unattended.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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