近年来,为了考查数学知识的应用,在各地的中考试卷上出现了大量的应用题.其中,一些应用题需构造函数模型来解.现采撷一例,供学习参考. In recent years, in order to examine the application of mathematics knowledge, there have been a large number of applied questions in various local examination papers. Among them, some application questions require a constructor function model to be solved. An example is now taken for reference.