计算下面各题(能简算的要简算)(1)6.25÷0.25×0.4

1个回答

  • 解题思路:(1)从左往右依次计算.

    (2)(5)(8)先算括号内的,再算括号外的.

    (3)运用加法结合律简算.

    (4)运用减法的性质简算.

    (6)运用乘法交换律与结合律简算.

    (7)运用除法的性质简算.

    (1)6.25÷0.25×0.4

    =25×0.4

    =10

    (2)68.04÷(0.21×3.6)

    =68.04÷0.756

    =90

    (3)0.486+0.01+3.99

    =0.486+(0.01+3.99)

    =0.486+4

    =4.486

    (4)19.75-6.45-3.55

    =19.75-(6.45+3.55)

    =19.75-10

    =9.75

    (5)2.02×(1.027÷0.26)

    =2.02×3.95

    =7.979

    (6)1.25×11×4×0.8

    =(1.25×0.8)×(11×4)

    =1×44

    =44

    (7)90÷25÷4

    =90÷(25×4)

    =90÷100

    =0.9

    (8)36÷(97.28÷0.32)

    =36÷304

    ≈0.12

    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: 考查了小数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律简便计算.