(1)(
+
+
)÷
(2)[1-(
+
)×
]÷
(3)6.46-(5.37-3.54)
(4)5.58-
+5.42-
.解:(1)(
+
+
)÷
,=(
)×48,=
×48+
×48+
×48,=40+28+18,
=86;
(2)[1-(
+
)×
]÷
,=[1-(
)×
]×
,=[1-
×
]×
,=[1-
]×
,=
,=1;
(3)6.46-(5.37-3.54),
=6.46-5.37+3.54,
=(6.46+3.54)-5.37,
=10-5.37,
=4.63;
(4)5.58-
+5.42-
,=(5.58+5.42)-(
),=11-1,
=10.
分析:(1)把除法改为乘法后发现,括号内的分数都能与48约分,所以用乘法分配律简算即可;
(2)先算小括号内的,再算中括号里的,最后算括号外的;
(3)先用减法的性质把原式变为6.46-5.37+3.54,再用加法结合律简算,即(6.46+3.54)-5.37;
(4)先利用加法交换律和结合律以及减法的性质进行简算.
点评:在做此类题时,注意从数字特点出发,巧妙灵活地应用运算性质、定律进行简算.