(1)128+750÷25×18
(2)(800×
-360)÷40 (3)
×
+
×
(4)[1-(
-
)]×
.解:(1)128+750÷25×18 =128+30×18,
=128+540,
=668;
(2)(800×
-360)÷40 =(640-360)÷40,
=280÷40,
=7;
(3)
×
+
×
=(
+
)×
,=2×
,=
;(4)[1-(
-
)]×
=[1-
]×
,=
×
,=
.分析:(1)(2)(4)根据四则混合运算的运算顺序计算即可:先算乘除,再算加减,有括号的要先算括号里面的.
(3)根据乘法分配律计算即可.
点评:当算式中同时含有中括号与小括号时,要注意先算小括号里面的,再算中括号里面的.