How smart are you a guy walks into a store and steals a 100

How smart are you?... a guy walks into a store and steals a $100 bill from the register without the owners knowledge. He comes back 5 minutes later and buys $70 worth of goods with the $100 bill the owner gives him $30 in change, how much money did the owner lose???

Solution

100$

For thsi look at the value of goods +money the guy has

70$ worth of goods and 30$ in change so total 100$.

So ownner lost 100$