She'll be 18 in about 6 minutes

A police man was on duty one night and he headed up to "Make out Mountain" to try to catch some couples in the act. When he got up there, he stopped at the first car where a couple sat, and was surprised to see the man was reading and the girl next to him was knitting.

He tapped on the window and said he was with the police department then asked how old he was and the guy said, "I'm 22, sir."

"Well, how old is she?" the officer then asked. Looking at his watch, the guy replied, "She'll be 18 in about 6 minutes."