(1)[4/7]+3.52+[3/7]+48% (2)[3/4]×[1/11]+[1/11×14] (3)[5/7]÷(
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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.