Test everyone: this is a math problem that can measure whether a person has a business mind.

Master Wang sells shoes. I bought a shoe for 45 yuan, and now it is on sale at a loss. Client 35 yuan bought a pair of shoes and gave them to Master Wang 100 RMB. Master Wang had no change, so he asked his neighbor to change it 100 yuan. Afterwards, neighbors found that the money was fake during the process of saving money, and it was confiscated by the bank. Master Wang also lost 100 to his neighbor. How much did Master Wang lose?

Answer:

There is no gain or loss between Master Wang and his neighbors.

People who buy shoes pay 100 yuan (0 yuan) to get a pair of shoes, and 90 yuan (a pair of 45 yuan and a pair of 90 yuan) gives change to 65 yuan, which is 155 yuan.

So Master Wang lost 155 yuan.