3/11÷2/17÷15/22 45×7/44 (7/12-5/36)÷1/6 2/7÷3/5+5/7×5/3 答案: 3/11÷2/17÷15/22 =3/11×17/2×22/15 =175 45×7/44 =(44+1)×7/44 =44×7/44+1×7/44 =7又7/44 点拨:形如(a+1)×ba的式子都能简算。 (7/12-5/36)÷1/6 =(7/12-5/36)×6 =7/12×6-5/36×6 =7/2-5/6 =16/6 =8/3 2/7÷3/5+5/7×5/3 =2/7×5/3+5/7×5/3 =5/3×(2/7+5/7) =53 |
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