When he was about 25, Jerry worked for a few years as a guard at a museum.

One day he was working in the dinosaur section when some tourists approached him. One of them asked,  "Can you tell us how old these dinosaur bones are?"

Jerry replied, "They are 3 million, three years, and ten months old."

"That's an awfully exact number," says the tourist.  "How do you know their age so precisely?"

Jerry answered, "Well, the dinosaur bones were three million years old when I started working here, and that was almost four years ago."

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Based on a *true* story???  I'm not sure. It's a story that has been passed around a lot, so ... (but I can believe that it happened <G>)