解:(1)345-2442÷37+34,
=345-66+34,
=279+34,
=313;
(2)(4-3.5×
![](http://thumb.zyjl.cn/pic5/latex/168.png)
)÷1
![](http://thumb.zyjl.cn/pic5/latex/113.png)
,
=(4-
![](http://thumb.zyjl.cn/pic5/latex/4579.png)
×
![](http://thumb.zyjl.cn/pic5/latex/168.png)
)×
![](http://thumb.zyjl.cn/pic5/latex/2105.png)
,
=(4-
![](http://thumb.zyjl.cn/pic5/latex/317.png)
)×
![](http://thumb.zyjl.cn/pic5/latex/2105.png)
,
=
![](http://thumb.zyjl.cn/pic5/latex/1231.png)
×
![](http://thumb.zyjl.cn/pic5/latex/2105.png)
,
=
![](http://thumb.zyjl.cn/pic5/latex/1205.png)
;
(3)180÷15+42×33-239,
=12+1386-239,
=1398-239,
=1159;
(4)8.59-2.07÷0.3×1.1,
=8.59-6.9×1.1,
=8.59-7.59,
=1;
(5)(2
![](http://thumb.zyjl.cn/pic5/latex/335.png)
-3.5÷2
![](http://thumb.zyjl.cn/pic5/latex/5192.png)
)×(2
![](http://thumb.zyjl.cn/pic5/latex/927.png)
+4.25),
=(
![](http://thumb.zyjl.cn/pic5/latex/153111.png)
-
![](http://thumb.zyjl.cn/pic5/latex/42957.png)
×
![](http://thumb.zyjl.cn/pic5/latex/15509.png)
)×(
![](http://thumb.zyjl.cn/pic5/latex/381444.png)
),
=(
![](http://thumb.zyjl.cn/pic5/latex/381445.png)
)×6
![](http://thumb.zyjl.cn/pic5/latex/168.png)
,
=(
![](http://thumb.zyjl.cn/pic5/latex/381446.png)
)×6
![](http://thumb.zyjl.cn/pic5/latex/168.png)
,
=
![](http://thumb.zyjl.cn/pic5/latex/381447.png)
,
=
![](http://thumb.zyjl.cn/pic5/latex/381448.png)
;
(6)[6-(
![](http://thumb.zyjl.cn/pic5/latex/2766.png)
×6.3+2
![](http://thumb.zyjl.cn/pic5/latex/2405.png)
)]÷0.15,
=[6-(2.8+2.3)]÷0.15,
=[6-5.1]÷0.15,
=0.9÷0.15,
=6.
分析:(1)345-2442÷37+34,此題應(yīng)先算除法,再算減法和加法;
(2)(4-3.5×
![](http://thumb.zyjl.cn/pic5/latex/168.png)
)÷1
![](http://thumb.zyjl.cn/pic5/latex/113.png)
,先算括號(hào)內(nèi)的,再算括號(hào)外的,在計(jì)算時(shí)把小數(shù)化為分?jǐn)?shù)較簡(jiǎn)便;
(3)180÷15+42×33-239,先算除法和乘法,再算加法和減法;
(4)8.59-2.07÷0.3×1.1,先算除法和乘法,最后算減法;
(5)(2
![](http://thumb.zyjl.cn/pic5/latex/335.png)
-3.5÷2
![](http://thumb.zyjl.cn/pic5/latex/5192.png)
)×(2
![](http://thumb.zyjl.cn/pic5/latex/927.png)
+4.25),注意把小數(shù)化為分?jǐn)?shù)計(jì)算較簡(jiǎn)便;
(6)[6-(
![](http://thumb.zyjl.cn/pic5/latex/2766.png)
×6.3+2
![](http://thumb.zyjl.cn/pic5/latex/2405.png)
)]÷0.15,此題把分?jǐn)?shù)化為小數(shù)計(jì)算較簡(jiǎn)便.
點(diǎn)評(píng):此題重點(diǎn)考查學(xué)生的運(yùn)算順序,在計(jì)算時(shí)要留心數(shù)的形式如何變化才能使計(jì)算簡(jiǎn)便的問題.