分与合——数感与数的运算探究与实践

Division and unification--Exploration and Practice of Number Sense and Number Operation

合与分可以统领加减乘除四则运算。加法和乘法是“合”,不同之处在于:加法是把相同的或者不同的几个数或数量合起来,乘法是把几个相同的数或者数量合起来(所以也说乘法是加法的简便运算)。

the sum and division can be used to operate the four operations of addition,subtraction,multiplication and division.Addition and multiplication are”addition”.The difference is that addition is the combination of the same or different Numbers or quantities.Multiplication is the combination of the same Numbers or quantities.