Four old mischievous Grandma's were sitting at a table in a nursing home. About then an old Grandpa walked in. One of the old Grandma's yelled out saying, 'We bet we can tell exactly how old you are. The old man said, 'There ain't no way you can guess it, you old fools.' One of the old Grandma's said, 'Sure we can! Just drop your pants & under shorts & we can tell your exact age.'
Embarrassed just a little, but anxious to prove they couldn't do it, he dropped his drawers. The Grandma's asked him to first turn around a couple of times & to jump up & down several times. Then they all piped up & said, '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 & grinning from ear to ear, all 4 old ladies happily yelled in
unison--'We were at your birthday party yesterday!'