Early one morning Hal, the owner of a hardware store, sells a mailbox for $25 to Courtney that cost him $20 wholesale. Courtney pays with a $100 bill and Hal discovers he doesn’t have enough change. He runs to the jewelry shop next door, where Jack, the owner, gives him change in exchange for the $100. Later that afternoon, Jack discovers the $100 bill is a counterfeit and Hal pays him $100 to make it right.
The total loss was $95.
-$20 = The wholesale cost of the mailbox
$100 = The money from Jack
-$75 = The change paid to Courtney
-$100 = To pay Jack back
-$20 + $100 – $75 – $100 = -$95
It’s easy to think Hal lost $195 but that fails to account for the $100 used to make the change, which came from Jack, not Hal. Jack paid $100 in exchange for a worthless piece of paper, so the $100 was initially Jack’s loss. Hal had made a $5 profit until Jack’s discovery. If you guessed $100, that’s arguably correct, but not making $5 in profit isn’t a loss in the strictest sense of the word.