A lady walks into a store and steals $100 bill from the register without the owners knowledge. She comes back 5 minutes later and buys $70 worth of goods with the $100 bill. The owner gives her $30 in change. How much did the owner lose? After the lady steals $100, the owner is down -$100. The lady comes back, and buys $70 worth of goods. At this point, the owner has -$100 + $70 = $-30. Next, the owner gives the lady another $30 in change, making the owner's loss -$30 - $30 = -$60.