题目内容
计算:[9
-(8-
)]÷2×
.
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考点:分数的巧算
专题:计算问题(巧算速算)
分析:把9
拆成9+
,中括号内运用减法的性质以及加法交换律与结合律简算即可.
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解答:
解:[9
-(8-
)]÷2×
=[9+
-8+
]÷2×
=[(9-8)+(
+
)]÷2×
=[1+1]÷2×
=2÷2×
=
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=[9+
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=[(9-8)+(
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=[1+1]÷2×
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=2÷2×
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=
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点评:仔细观察算式特点,灵活运用运算定律或运算技巧,进行简算.
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