× = | × = | × = | ×2= | 5- = |
12× = | 1÷ = | + × = | (6+ )× = | ×39× = |
× = ; | × = ; | × = ; | ×2= ; | 5- =4 ; |
12× =9; | 1÷ =16; | + × = ; | (6+ )× =5 ; | ×39× =10 . |
分析:根据分数四则混合运算的顺序,按照分数加、减、乘、除法的计算法则,直接进行口算即可.其中(6
)×
,可以运用乘法分配律进行简算.点评:此题考查的目的是掌握分数四则混合运算的顺序、以及分数加、减、乘、除法的计算法则,并且能够正确熟练地进行口算,提高口算能力.
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=
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×
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=
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×39×
=
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