Standard answer: First of all, how much did the customer who took the counterfeit money charge Ms. Wang? The answer is a pair of shoes given to him by Ms. Wang from 45 yuan and 70 yuan (because there are 30 pairs on sale). This is the money the customer got from Ms. Wang (compared with Ms. Wang, it is equivalent to losing a pair of shoes from 30 yuan +70 yuan, that is 1008). Only Ms. Wang's loss is counted here, so Ms. Wang lost 1 15 yuan to her customers. Then, Ms. Wang and the temporary store changed 100 yuan, but the temporary store later found the counterfeit money received, and of course asked Ms. Wang to return 100 yuan. But at this time, after Ms. Wang gave 70 yuan, a customer who spent counterfeit money, she only had 30 yuan's real money, so she had to take out 70 yuan from her pocket to supply the boy in the temporary shop. At this time, some people will say that Ms. Wang's loss is 45+70+70= 185, or some friends who can't think will work out other answers. Haha, in fact, Ms. Wang lost 1 15 yuan, because no matter how many twists and turns there are in this topic, it is ever-changing. But think about it, only the real RMB from 70 yuan and a pair of shoes from 45 yuan are taken out of Ms. Wang's own pocket.