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A farmer had 5 female pigs. Times were hard, so he decided to
take them to the county fair and sell them.

At the fair, he met another farmer who owned five male pigs.
After talking a bit, they decided they'd mate the pigs and split
everything 50/50. The farmers lived sixty miles apart, so they
agreed to drive thirty miles each and find a field in which to let
the pigs mate.

The first morning, the farmer with the female pigs got up at 5:00
AM, loaded the pigs into the Station wagon, the only vehicle they
had, and drove the thirty miles.

While the pigs were mating, he asked the other farmer, "How will
I know if they are pregnant?"

The other farmer replied, "If they're lying in the grass tomorrow
morning, they're pregnant. If they're in the mud, they're not."

The next morning the pigs were rolling in the mud, so he hosed
them off, loaded them into the family station wagon again and
proceeded to try again. This continued each morning for more
than a week and both farmers were worn out.

The next morning he was too tired to get out of bed. He called
to his wife, "Honey, please look outside and tell me whether
the pigs are in the mud or in the grass."

"Neither," yelled his wife, "they're in the station wagon and one
of them is honking the horn."
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