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Getting Across the River

Getting Across the River, a selection of answers from the Dr. Math archives.

Wolf, Cabbage, Goat, and River

A man has a goat, a wolf and a cabbage. He must cross a river in a boat that will only carry one item at a time...

Farmer, Goat, Wolf, and Cabbage Cross a River

Fewest number of trips a farmer can make to get a goat, wolf, and cabbage across a river.

Farmer Crossing a River

A farmer is taking his prize lettuce, lion, llama, and pet leviathan (a unique creature that eats llamas and lions unless a lettuce is present) to market...

Crossing a River: Cannibals and Missionaries

Three missionaries and three cannibals wish to cross a river using a single boat that will hold only two people. If at any time the cannibals outnumber the missionaries, those missionaries will be eaten...

Wilbert the Wonder Dog

Five masters and their five dogs need to cross a river.

Crossing the Bridge

Four men want to cross a bridge but only two may cross at a time...