( )÷(1- )= | 6.8×2.5+2.5×3.2= |
36÷[(![]() )×3]= | = |
= | = |
+
)÷(1-
),=
÷
,=
×
,=
;(2)6.8×2.5+2.5×3.2,
=(6.8+3.2)×2.5,
=10×2.5,
=25;
(3)36÷[(

)×3],=36÷[

×3],=36÷
,=36×
,=43.2;
(4)
÷
-
×
,=
×
-
×
,=0;
(5)
÷5+
÷7,=
×
+
×
,=
×(
+
),=
×
,=
;(6)
×1
+1.4×
,=
×1.4+1.4×
,=(
+
)×1.4,=1×1.4,
=1.4.
分析:(1)两个括号同时计算,然后算除法;
(2)运用乘法分配律简算:
(3)先去小括号,中括号内约分计算,最后算括号外的;
(4)把除法转化为乘法,发现减号前后算式相等,故结果为0;
(5)把除法转化为乘法,运用乘法分配律简算;
(6)把1
化为小数,运用乘法分配律简算.点评:完成本题要注意分析式中数据,运用合适的简便方法计算.
)÷(1-
=
=
=