解:(1)(284+16)×(512-8208÷18)+
×
+
,
=300×(512-456)
,
=300×56+
,
=16800
,
=16800
;
(2)6-1.19×3-0.43+
+
÷
,
=6-3.57-0.43+0.2+
90,
=6-3.57-0.43+2.2,
=6-(3.57+0.43)+2.2,
=2+2.2,
=4.2;
(3)3.2×(1.5+2.5)÷1.6+14×
-
×
,
=3.2×4÷1.6+
,
=12.8÷1.6+
-
,
=8
,
=8
;
(4)27.85-(7.85+3.4)+
-
×
,
=(27.85-7.85-3.4)+
,
=(20-3.4)+
,
=16
+
,
=16
,
=16
;
分析:運(yùn)用分?jǐn)?shù),小數(shù)的四則混合運(yùn)算的順序及分?jǐn)?shù),小數(shù)的加減乘除法的計(jì)算法則進(jìn)行計(jì)算即可.
(1)先計(jì)算小括號(hào)內(nèi)部的再計(jì)算括號(hào)外面的.
(2)計(jì)算6-3.57-0.43運(yùn)用減法的性質(zhì)進(jìn)行計(jì)算較簡(jiǎn)便.
(3)3.2×(1.5+2.5)÷1.6運(yùn)用小數(shù)的加減乘除法的計(jì)算法則進(jìn)行計(jì)算即可,14×
-
×
,運(yùn)用分?jǐn)?shù)的乘法的計(jì)算法則進(jìn)行計(jì)算.
(4)27.85-(7.85+3.4)運(yùn)用小數(shù)的加減法的計(jì)算法則進(jìn)行計(jì)算即可,計(jì)算
-
×
運(yùn)用乘法的分配律進(jìn)行計(jì)算即可.
點(diǎn)評(píng):考查了運(yùn)算定律與簡(jiǎn)便運(yùn)算,四則混合運(yùn)算.注意運(yùn)算順序和運(yùn)算法則,靈活運(yùn)用所學(xué)的運(yùn)算律簡(jiǎn)便計(jì)算.