This is a primary school math problem to buy stationery. According to the topic, how many pencil boxes can I buy with the money for 1 schoolbag? We can know that the price of schoolbags is definitely the highest, so it is 150 yuan. We don't know the price of the pencil case, so we can directly take 150 and divide it by the other two prices to get an integer and a decimal. This topic will not involve decimals, so we know that the price of the pencil case is.