说到简便运算,会令许多老师和学生头疼,什么加法交换律、加法结合律,什么a-b-c=a-(b+c),a-(b-c)=a-b+c……种类繁多,灵活多变,很难掌握。导致考试卷上错得最多的往往是简便运算题。比如:23.5+10.73-3.5=34.23-3.5=30.73虽然答案是正确的,但没有使用简便方法,不能算对。又如:1÷ When it comes to simple operation, many teachers and students will have a headache, what is the addition exchange law, and the law of addition and combination? What is abc = a- (b + c), a- (bc) = a-b + c? Changeable, difficult to master. It is often easy to ask for the most wrongly written test paper. For example: 23.5 + 10.73-3.5 = 34.23-3.5 = 30.73 Although the answer is correct, there is no easy way to use it. Another example: 1 ÷