| 605×2= | 680+340= | 560-240= | 400×5= | 63÷7= | 456×0= |
| 840+630= | 7×110= | 1- = | + = | - = | + = |
| 解:605×2=1210, | 680+340=1020, | 560-240=320, | 400×5=2000, | 63÷7=9, | 456×0=0, |
| 840+630=1470, | 7×110=770, | 1- = , | + =1, | - =0, | + = . |
分析:根据整数和分数加减乘除的计算方法进行计算即可.
点评:口算时,注意运算符号和数据,然后再进一步计算即可.
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