[答案]五年級奧數(shù)天天練2012.5.30

字號:


        【計算】
    1.難度:★★
      (1)2003×2001÷111+2003×73÷37
    (2)412×0.81+11×+53.7×1.9
      【分析】
        (1)原式=2003×2001÷111+2003×73×3÷(37×3)
                 =2003×(2001+73×3)÷111
             =2003×2220÷111=40060
    (2)原式=41.2×8.1+11×(9+0.25)+(41.2+12.5)×1.9
    =41.2×8.1+41.2×1.9+12.5×1.9+11×9+11×0.25
    =41.2×(8.1+1.9)+(10+2.5)×1.9+99+11×0.25
    =412+10×1.9+2.5×1.9+99+11×0.25=412+19+99+(11+19)×0.25
    =410+2+20-1+100-1+7.5=537.5
     
     
    2.難度:★★★
        【分析】