A Family Problem

A man, his wife, and their two sons desire to cross a river.  They have a boat that will carry only 100 lbs.  The man weighs 100 lbs, the wife weighs 100 lbs, and the sons each weigh 50 lbs.  How can they all cross this river in this boat?

Soulé's Philosophic Practical Mathematics, George Soulé, 1905

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