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Three jealous couples and a two-seat boat

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Three married couples must cross a river in a boat that holds two people. Everyone can row. The husbands are jealous: no wife may be on a bank or in the boat with another man unless her own husband is also there. Women may be alone together, and men may be alone together.

What is the fewest number of one-way crossings, and what is the sequence?

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Send the women first. The awkward moment is bringing the last husband over; expect one crossing where a couple comes back together.

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