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It is believed that this problem was invented by Edouard Lucas and that he also invented the well known Frogs problem. He was a French mathematician who lived in the nineteenth century.

Every day at noon (Greenwich Mean Time) a boat leaves Le Havre for New York while another boat leaves New York for Le Havre.
The ocean crossing takes seven days and seven nights.
How many boats on the New York to Le Havre route will the boat leaving Le Havre today meet during its journey to New York?
Does it change your answer if the boats leave Le Havre and New York at noon local time. How can you illustrate your answer?

See Buses for a similar problem.