A Scotsman phones a dentist to inquire about the cost for a tooth extraction.
"£85 for an extraction, sir" the dentist replied.
"£85!!! Huv ye no' got anythin' cheaper?"
"That's the normal charge," said the dentist.
"Whit aboot if ye didnae use any anaesthetic?"
"That's unusual, sir, but I could do it and knock £15 off."
"Whit aboot if ye used one of your dentist trainees and still without an anaesthetic?"
"I can't guarantee their professionalism and it'll be painful. But the price could drop to £40"
"How aboot if ye make it a trainin' session, ave yer student do the extraction, with the other students watchin' and learnin'?"
"It'll be good for the students", mulled the dentist.
"I'll charge you £5, but it's going to be very traumatic."
"Och, now yer talkin' laddie! It's a deal," said the Scotsman."Can ye confirm an appointment for the wife next Tuesday then?"