A shepherd needs to cross a river with a wolf, a goat, and a cabbage. However, his boat can only hold himself and one item at a time. If left alone, the wolf eats the goat, and the goat eats the cabbage. How can the shepherd cross safely in the fewest round trips?
Take the goat first, return alone. Take the wolf (or cabbage), bring the goat back. Take the cabbage (or wolf), return alone. Finally, take the goat across.
This is the classic river crossing puzzle. Minimum round trips require taking the goat across, returning empty, taking the wolf across, bringing the goat back to the starting shore, taking the cabbage across, returning empty, and finally bringing the goat across.
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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