A gynaecologist decides to quit his job after becoming disillusioned with working in hospitals. He thinks he will have a complete change of career and signs up at the local tech to learn how to be a mechanic. He loves the course and throws himself into it and when he sits his final exams he's sure he's done well; even so, he is taken aback to see he has been given a score of 150%. He goes to speak to his course tutor and asks if it is perhaps a mistake. The tutor says: "no, that's your mark right enough - you took the engine apart perfectly, that's 50% of the mark, and you put it back together again faultlessy, which is another 50%. I gave you the extra 50% because you did it all through the exhaust pipe and I've never seen that in my life before!"