陈德前近年来,在中考的数学试卷中,出现了一种新题型———说理题.这类题要求考生不仅要计算、判断、推理和论证,还要说明推理的依据及其思想方法.下面举例说明说理题的解法.茯一、运用代数来说理例1 甲、乙两人在同一粮店购买粮食(设两次单价不同),甲每次购粮100千克,乙每次 In recent years, in Chen Deqian’s mathematics test, a new type of question has emerged, which is called the theory. This type of question requires candidates not only to calculate, judge, reason and demonstrate, but also to explain the basis of reasoning and their thinking and methods. The following example illustrates the solution to the problem. First, use algebra for example 1 A, B two people in the same food store to buy food (set twice the unit price is different), a purchase of 100 kg each time, B each time