math challenge

Week of April 22 - 28, 1996

Ferry Crossing

Two elves and two leprechauns came to an enormous lake which they had to cross in order to escape the ogre. They had only a ferry boat, which had a maximum capacity of 40 pounds. Each of the elves weighed 20 pounds, and each of the leprechauns weighed 40 pounds. How can they get across the lake?

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