英语笑话:An Exact Number（准确数字）

A tourist was visiting New Mexico and was amazed at the dinosaur bones lying about.

How old are these bones? the tourist asked an elderly Native American, who served as a guide.

Exactly one hundred million and three years old.

How can you be so sure? inquired the tourist.

Well, replied the guide, a geologist came by here and told me these bones were one hundred million years old, and that was exactly three years ago.