所谓合理想象,这里是指在用算术法解应用题而进行的想象的过程中,保持题目里的已知数量和数量关系不变,但除此之外的人和物皆可按解题的需要而发生变化,正是在这种变化中找到解题之法。合理想象必须根据题目来进行,由于算术题纷繁多样,因此合理想象也是五花八门。本文只讨论其中的两种方法:“分合法”与“分组法”。 The so-called rational imagination, here refers to maintaining the known quantity and quantity relationship in the subject in the process of imagination performed by solving mathematics problems by arithmetic, but other people and objects can solve the problem. Need to change, it is in this change to find the solution to the problem. Reasonable imagination must be carried out according to the subject. Because of the numerous and varied arithmetic problems, reasonable imagination is also varied. This article only discusses two methods: “legal legalization” and “grouping method.”