Well this is an extra-credit but I really want to get it so here's the question (It's math btw)
The Counterfeit Problem:
You are the owner of a small sporting goods
store. Just after opening the store one
morning, a woman comes in and buys a pair of
Nike (or Adidas) running shoes (she's running in
a marathon) for $67.95. She pays for them
with a $100 bill. Not having change on hand
yet, you go next door to the florist shop and
ask the owner if he can change the $100 bill.
He can and does, giving you the right 'type' of
change so you can give change to the woman.
You return and give the customer the correct
change. She leaves with the shoes and the
change. Several hours later, the florist comes
in and tells you that the $100 bill is counterfeit.
After you both inspect it, you agree that it is
counterfeit. Feeling responsible, you give the
florist $100 from your till, which now has an
adequate amount of change, and he returns to
his shop with the $100.
Question:
How much, if anything, did you lose in the
transaction? (Consider the shoes to have a
value of $67.95, not a lesser wholesale value).