This popular math puzzle confuses people because many accidentally count the same $100 twice. In the scenario, a thief steals $100 from a store, then later uses that same stolen bill to buy $70 worth of goods and receives $30 in change.
Many argue over whether the store lost $200, $170, or $130, but the correct answer is much simpler. Since the stolen $100 bill was returned to the register during the purchase, the store only lost the $70 in merchandise plus the $30 given as change.
In the end, the store’s total loss is exactly $100. The puzzle tricks people into overthinking what was actually lost.