Three mischievous grandmas were sitting on a bench outside a nursing home. An old man walked by, and one of the grandmas yelled out, “Bet we can guess exactly how old you are.”
The old man said, “There ain’t no way you can guess it, you three old fools.”
One of the grandmas said, “SURE WE CAN! JUST DROP YOUR PANTS AND WE WILL TELL YOU YOUR EXACT AGE.”
Slightly embarrassed, the old man dropped his pants.
The grandmas stared at him for a while, asked him to turn around a couple of times, jump up and down for a little while, and then they all piped up and said, “YOU’RE 91 YEARS OLD!”
“How in the world did you guess?” the old man said in shock. The grandmas snickered and replied, “Because we were at your birthday party yesterday!”