A gynecologist was getting sick of his job and decided that he
needed a career change.  He'd always enjoyed tinkering with
engines so thought he'd become a mechanic.

So he went along to mechanics school and the final test was to
strip the engine completely and reassemble it - obviously back
into perfect working order.  So our gynecologist friend did the
test and anxiously awaited the result.

The day he received the results he got quite a surprise, he
got 150%!  He quickly phoned the instructor and queried the
mark.  The instructor said, "No no that's right.  First I gave
you 50% for stripping down the engine -- a very thorough job.
Next I gave you 50% for reassembling it - a fantastic job
really.  Then I gave you a 50% bonus for doing it all through
the muffler."