One day, a man walks into a dentist's office and asks how much it
will cost to extract wisdom teeth.

"Eighty dollars," the dentist says.
"Isn't there a cheaper way?"

"Well," the dentist says, "if you don't use an anaesthetic, I can
knock it down to $60."
"That's still too expensive," the man says.
"Okay," says the dentist.  "If I save on anesthesia and simply
rip the teeth out with a pair of pliers, I could get away with charging $20."

"Marvelous," says the man, "book my wife for next Tuesday!"