A customer enters a store & purchases slippers for $5, paying for the purchase with $20 bill. The merchant, unable to make change, ask the grocer next door to change the bill. The merchant then gives the customer the slippers & $15 change. After the customer, leaves the grocer discovers that the $20 bill is counterfeit & demands that the shoe store owner make good on it. The shoe store owner does so, & by law is obligated to turn the counterfeit bill over to the FBI. How much does the shoe store owner lose in this transaction?

2 answers

I think he lost $20 + the cost of the slippers. Or is this a trick question?
Suppose the merchant has only a $20 bill in his till. The customer comes in with the (counterfeit) $20, goes next door to the grocer and then gets, let's say, four $5 bills. He comes back and gives the customer three of those for his $15 change and then puts the fourth $5 bill in his till. This means, right now he is up $5 for $25 in his till. Later, the grocer next door comes in with the counterfeit bill and the merchant must give him $20, leaving $5 in his till. Considering he SHOULD have $25 in the cash register, I agree that he is out $20 [plus the cost of buying the slippers].