简便运算是利用某些算式和数据的特点,根据四则运算定律、性质以及和差积商的变化规律使运算过程简化的一种算法。这里,简介小学数学教材中几种常见的简便运算方法及其理论根据。一、分组凑整法把能凑成整十、整百……的数分成一组,再进行运算的方法叫做分组凑整法。 1.根据加法交换律和结合律分组。这类算式和数据的特点:(1)是求几个数的和;(2)分组后所得的和能成为整十,整百……如 2+4+6+……+18+20=(2+18)+(4+16)+(6+14)+(8 Simple operation is the use of some of the characteristics of arithmetic and data, according to the four law of operation, the nature and the sum of the product of the difference and the change of the algorithm to simplify the operation of an algorithm. Here, a brief introduction of several common primary mathematics textbooks and easy operation method and its theoretical basis. First, the packet rounding law to make up the whole ten, the whole number of 100 ... ... into a group, and then the method of operation is called group rounding method. 1. According to the law of addition and combination law grouping. The characteristics of such calculations and data: (1) is the sum of a few numbers; (2) the sum obtained after the grouping can become the whole ten, the whole one hundred ... as 2 + 4 + 6 + ... + 18 + 20 = (2 + 18) + (4 + 16) + (6 + 14) + (8)