(2012•蕲春县模拟) (1)[4/7]+3.52+[3/7]+48% (2)[3/4]×[1/11]+[1/11×1

1个回答

  • 解题思路:(1)运用加法交换律与结合律简算;

    (2)(4)运用乘法分配律简算;

    (3)先算括号内的除法,再算括号内的减法,最后算括号外的除法;

    (5)把原式变为1000÷(4×8)÷[1/4]÷[1/8],在把除法变为乘法,计算即可;

    (6)把分数变为小数,运用加法交换律与结合律简算.

    (1)[4/7]+3.52+[3/7]+48%,

    =([4/7]+[3/7])+(3.52+48%),

    =1+4,

    =5;

    (2)[3/4]×[1/11]+[1/11×

    1

    4],

    =([3/4]+[1/4])×[1/11],

    =1×[1/11],

    =[1/11];

    (3)[5/7]÷(5-3.9×[2/3]),

    =[5/7]÷(5-2.6),

    =[5/7]÷2.4,

    =[5/7]÷[12/5],

    =[5/7]×[5/12],

    =[25/84];

    (4)25-25×[99/100],

    =25×(1-[99/100]),

    =25×[1/100],

    =[1/4];

    (5)1000÷32÷0.25÷0.125,

    =1000÷(4×8)÷[1/4]÷[1/8],

    =1000÷4÷8×4×8,

    =1000×(4÷4)×(8÷8),

    =1000;

    (6)38[3/4]-15.38+61.25-4.62,

    =38.75-15.38+61.25-4.62,

    =(38.75+61.25)-(15.38+4.62),

    =100-20,

    =80.

    点评:

    本题考点: 整数、分数、小数、百分数四则混合运算;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律简便计算.