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Three elderly and mischievous Grannies were sitting on a bench outside the retirement home.

About then an old Grandpa walked by, and one of the grannies yelled out: "Bet we can tell exactly how old you are."

Grandpa said, "No way you can guess it, you old fools."

One of the Grannies said, "Sure we can! Just drop your pants and undershorts and we can tell your exact age."

Embarrassed just a little, but very anxious to prove they couldn't do it, Gramps dropped his drawers.

The Grannies asked him to first turn around a couple of times and to jump up and down.

Then the three of them yelled: "You're 87 years old!"

Standing with his pants down around his ankles, the old gent asked, "How in the world did you guess?"

Slapping their knees and grinning from ear to ear, all three Grannies happily yelled in unison -- "We were at your birthday party yesterday."
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