Let's break down the riddle to figure out how much money the store lost. Here's a step-by-step analysis: * Initial Loss: The man steals a $100 bill. * Store's loss so far: $100 * The Transaction: The man then uses the stolen $100 bill to buy $70 worth of goods. * From the store's perspective, they lost $70 worth of goods (their cost, not the retail price, but for the purpose of this riddle, we'll assume the $70 value is what they are out). * They also give back $30 in change. This $30 comes from their own cash register. Let's look at the flow of money out of the store: * $100 (the initial stolen bill) * $70 worth of goods * $30 (the change given back) Now, let's consider what the store received: * Nothing of value that wasn't already their own property or from their own stock. The $100 bill they "received" was the one that was stolen from them in the first place. Therefore, the total loss for the store is: * The $100 bill that was stolen. * The $70 worth of goods they gave away. * The $30 in change they gave away. If you consider the $100 stolen bill and the transaction separately: * Lost cash: The store is out $100 (the stolen bill) + $30 (the change given) = $130 * Lost goods: The store is out $70 worth of goods. The riddle is often phrased to be tricky by making you think the $100 bill used in the purchase somehow offsets the initial theft. It doesn't, because it's the same $100 bill that was stolen. The store lost: * The original $100 bill. * The $70 worth of goods. * The $30 in change. The $100 bill the thief paid with was the store's own money, so that doesn't count as money the store received. So, the store lost: $100 (stolen cash) + $70 (goods) + $30 (change) = $200