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A farmer is heading home from the market with a fox, a goose, and a bag of corn. He needs to rent a boat but can only bring one item at a time with him to the other side of the river. If he leaves the fox alone with the goose, the fox will eat the goose. If he leaves the goose alone with the corn, the goose will eat the corn. How does the farmer get all three items to the other side of the river safely?
Bring the goose across first, then the fox, and then bring the goose back with him across to get the corn, leave the goose, drop off the corn, and go back for the goose.