[0:00]This situation confuses a lot of people, so watch closely.
[0:04]Two friends walk into a shop and order an item that cost 50.
[0:08]One of them pays with a 100 bill.
[0:11]The cashier gives him the item and 50 in change.
[0:14]A moment later, his friend forgets she already has the 50, so she gives the cashier 50 and asks for the 100 back.
[0:23]Then they run away, so who actually made a profit here?
