计算.(能简算的要简算) ①0.25×6.82×4 ②1.344+0.162÷4 ③12.68-4.8-3.68 ④3.

1个回答

  • 解题思路:(1)运用乘法的交换律、结合律进行简算,

    (2)先算除法,再算加法,

    (3)运用减法的运算定律进行简算,先减去3.68,再减去4.8,

    (4)先分别算出除法和乘法,再算减法,

    (5)从左向右进行计算即可,

    (6)先算小括号里的除法,再算小括号里的加法,最后算括号外的除法,

    (7)先算小括号里的减法,再运用乘法的分配律进行简算,

    (8)先算小括号里的减法,再算中括号里的除法,最后算括号外的乘法.

    (1)0.25×6.82×4,

    =(0.25×4)×6.82,

    =1×6.82,

    =6.82;

    (2)1.344+0.162÷4,

    =1.344+0.0405,

    =1.3845;

    (3)12.68-4.8-3.68,

    =12.68-3.68-4.8,

    =9-4.8,

    =4.2;

    (4)3.6÷1.2-0.8×2.7,

    =3-2.16,

    =0.84;

    (5)9.2×1.05÷3.4,

    =9.66÷3.4,

    ≈2.84

    (6)(2.6+3.2÷1.28)÷1.7,

    =(2.6+2.5)÷1.7,

    =5.1÷1.7,

    =3.00;

    (7)6.83×(3.8-2.3)+1.5×3.7,

    =6.83×1.5+1.5×3.7,

    =(6.83+3.7)×1.5,

    =10.53×1.5,

    =15.795;

    (8)4.5×[7.68÷(8.2-1.8)],

    =4.5×[7.68÷6.4],

    =4.5×1.2,

    =5.4.

    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: 此题考查了小数四则混合运算的顺序,灵活运用运算定律进行简算,要细心、认真计算,防止出错.