用递等式计算(能用简便方法计算的尽可能用简算)

1个回答

  • (12)0.4×(3.2-0.8)÷0.15,

    =0.4×2.4÷0.15,

    =0.96÷0.15,

    =6.4;

    (13)5.7+1.9×0.2÷7.6,

    =5.7+0.38÷7.6,

    =5.7+0.05,

    =5.75;

    (14)32.4×6.3+32.4×3.7,

    =32.4×(6.3+3.7),

    =32.4×10,

    =324;

    (15)18.2-10.6×(0.9-0.75),

    =18.2-10.6×0.15,

    =18.2-1.59,

    =16.61;

    (16)0.25×3.85×40,

    =0.25×40×3.85,

    =10×3.85,

    =38.5;

    (17)1.46×3.5+3.5×4.54,

    =3.5×(1.46+4.54),

    =3.5×6,

    =21.