A shepherd needs to cross a river with a wolf, a goat, and a cabbage. He has a boat that can only hold himself and one item at a time. However, if left alone together, the wolf will eat the goat, and the goat will eat the cabbage. What is the minimum number of one-way trips the shepherd must make to transport everything across safely?
7
Trip 1: Take goat across (leave wolf and cabbage). Trip 2: Return empty. Trip 3: Take wolf across, bring goat back. Trip 4: Take cabbage across (leave goat). Trip 5: Return empty. Trip 6: Take goat across. Trip 7: Arrive with all items. Total one-way legs: 7.
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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