Three mischievous old grannies were sitting on a bench outside a nursing home when an elderly gentleman walked past them.

One of the women called out, “Hey! We bet we can tell exactly how old you are!”

The old man stopped, looked at them, and laughed.

“There’s absolutely no way you can guess my age, you old fools.”

Another granny smiled confidently.

“Oh, yes, we can. All you have to do is drop your pants and underwear, and we’ll tell you your exact age.”

The old man was slightly embarrassed, but he was also eager to prove that they were bluffing.

After looking around to make sure nobody else was watching, he lowered his trousers.

The three grannies studied him carefully.

“Now turn around a few times,” one of them instructed.

He slowly turned around.

“Good. Now jump up and down a few times,” another added.

Although increasingly confused, the old man did exactly as they asked.

The women whispered among themselves for a moment before suddenly shouting together:

“You’re 87 years old!”

Standing there with his trousers around his ankles, the astonished old man asked:

“How in the world did you guess?”

Slapping their knees and grinning from ear to ear, the three old ladies happily yelled in unison…

“We were at your birthday party yesterday!”