复习提要数的运算是小学数学中最基本的内容之一,对于整数、小数、分数的四则运算,以及它们的混合运算,不仅要计算正确,而且要做到计算方法合理、灵活。为了达到这个要求,在复习四则运算时,要做到一个“理解”,四个“掌握”。即:理解四则运算的意义;掌握加、减、乘、除的计算法则,掌握加法与减法,乘法与除法的关系,掌握四则混合运算的顺序,掌握运算定律和性质。另外,要注意两点:一是对于一些基本计算,要加强口算练习,达到一定的熟练程度;二是对于四则混合运 The operation of review digests is one of the most basic contents in elementary mathematics. For the four arithmetic operations of integers, decimals and fractions, as well as their mixed operation, not only the calculation is correct, but also the calculation method is reasonable and flexible. In order to meet this requirement, when reviewing the four operations, we must achieve an “understanding” and four “mastery.” That is: to understand the meaning of the four operations; grasp the addition, subtraction, multiplication and division of the rules, master addition and subtraction, multiplication and division, grasp the order of the four mixed operations, master the law of operation and nature. In addition, we should pay attention to two points: First, for some basic calculations, we should strengthen the mouth exercise, to a certain degree of proficiency; Second, for the four mixed transport