| 637-363= | 0.5× = | 3.25× = | 31-3.1= | = |
| 25+25×0= | ![]() = | ÷ = | × ÷ × = | 1- - = |
| 解:637-363=274, | 0.5× = , | 3.25× =1, | 31-3.1=27.9, | = , |
| 25+25×0=25, | ![]() =1, | ÷ = , | × ÷ × = , | 1- - = . |
分析:
,25+25×0先算乘法,再算加法;
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先把除法变成乘法,再运用乘法结合律简算;1-
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根据减法的性质简算;其它题目根据运算法则直接求解.
点评:口算题目要求快速准确,能运用简算方法的要简算.
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