笔者根据小学数学教学的经验,将小学加减法简算进行了分类归纳,我把小学数学的加减法简算归纳为四种类型:1、多加几就减几。这种类型的简算题目具有下面的特征,第一个特征是加法,第二个特征是其中一个加数接近整十 The author based on the experience of primary school mathematics teaching, the primary school addition and subtraction simple summed up the classification, I added primary school mathematics addition and subtraction simple summed up into four types: 1, plus a few more. The simplest topic of this type has the following features, the first feature is addition, the second feature is that one of the addends is nearly an entire ten