用递等式计算,能简便计算的要简算.

1个回答

  • 解题思路:(1)(6)依据四则运算顺序:先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的顺序即可解答,

    (2)(3)(4)(5)运用乘法分配律解答.

    (1)2.01×1.53÷0.18,

    =3.0753÷0.18,

    =17.085;

    (2)5.86×99.4+5.86×0.6,

    =5.86×(99.4+0.6),

    =5.86×100,

    =586;

    (3)2.2×2.2+2.2×7.8,

    =2.2×(2.2+7.8),

    =2.2×10,

    =22;

    (4)0.25×(4.83-0.85),

    =0.25×3.98,

    =0.25×4-0.25×0.02,

    =1-0.005,

    =0.995;

    (5)(12.5+1.25+0.125)×8,

    =12.5×8+1.25×8+0.125×8,

    =100+10+1,

    =110+1,

    =111;

    (6)(148.4-90.85)÷2.5,

    =57.55÷2.5,

    =23.02.

    点评:

    本题考点: 小数四则混合运算;运算定律与简便运算.

    考点点评: 本题考查知识点:(1)依据四则运算计算方法正确进行计算,(2)正确运用乘法分配律解决问题.