脱式计算.(能简算的要简算)5.4×5.08+3.6×5.08+5.08;

1个回答

  • 解题思路:(1)根据乘法分配律进行简算;

    (2)根据乘法交换律进行简算;

    (3)先算加法,再算中括号里面的除法,再算减法,最后算括号外面的除法;

    (4)先算小括号里面的减法,再算中括号里面的乘法,再算中括号里面的减法,最后算括号外面的乘法.

    (1)5.4×5.08+3.6×5.08+5.08

    =(5.4+3.6+1)×5.08

    =10×5.08

    =50.8;

    (2)0.25×588.5×400

    =0.25×400×588.5

    =100×588.5

    =58850;

    (3)[10.31-(4.86+1.03)÷1.9]÷0.125

    =[10.31-5.89÷1.9]÷0.125

    =[10.31-3.1]÷0.125

    =7.21÷0.125

    =57.68;

    (4)[(6.1-4.6)×0.8-1]×0.4

    =[1.5×0.8-1]×0.4

    =[1.2-1]×0.4

    =0.2×0.4

    =0.08.

    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: 考查了运算定律与简便运算,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.