最新苏教版加法交换律教学设计 加法交换律教学重点(大全12篇)

在日常学习、工作或生活中,大家总少不了接触作文或者范文吧,通过文章可以把我们那些零零散散的思想,聚集在一块。相信许多人会觉得范文很难写?接下来小编就给大家介绍一下优秀的范文该怎么写,我们一起来看一看吧。

苏教版加法交换律教学设计 加法交换律教学重点篇一

教材p28页例1,p30页练习相关习题。

教学目标

1、知识与技能:

结合具体的情境,引导学生认识和理解加法交换律的含义。

2、过程与方法:能用字母式子表示加法交换律,初步学会应用加法交换律进行一些简便运算。

3、情感态度与价值观:

①体验自主探索、合作交流,感受成功的愉悦,树立学习数学的自信心,发展对数学的积极情感。

②培养学生观察,比较,抽象,概括的初步思维能力。

教学重点

认识和理解加法交换律的含义。

教学难点

引导学生抽象,概括加法交换律。

教学用具

多媒体课件。

教学过程

(一)出示自学提纲

自学提纲(教材p28页例1,并完成自学提纲问题,将不会的问题做标注)

1、根据例1情境图中信息列出算式。

2、用你喜欢的方法尝试计算

3、同桌交流自己的算法

4、教师板书出学生的算式及答案

40+56=96(千米) 56+40=96(千米)

5、对比上面的两道算式,你发现了什么?用自己的话说一说。

(二)学生自学(学生对照自学提纲,自学教材p28页例1,并完成自学提纲问题,将不会的问题做标注)

(学生自学,教师在不干扰学生的前提下巡回指导,发现共性问题,以掌握学生学情)

(三)自学检测

1、填空

387+425=( )+ 387 525+( )=137+ 525

300+600=( )+( ) ( )+65=( )+35

甲数+乙数=( )+( ) 偶数+( )=奇数+( )

2、连线

56+68 50+b

b+50 68+56

(一)小组互探(自学中遇到不会的问题,同桌或学习小组内互相交流。把小组也解决不了的问题记好,到学生质疑时提出,让其他学习小组或教师讲解。)

(引导学生正确地计算,鼓励学生分工合作,探索交流,教师巡回辅导,发现、收集学生存在的问题)

(二)师生互探

1、解答各小组自学中遇到不会的问题。

(1)让学生提出不会的问题,并让学生解决。

(2)教师引导学生解决学生还遗留的问题。

(3)如何用字母表示加法交换律和结合律?

(4)用字母表示这些运算定律有什么优点?

2、教师有针对性地请不同做法的同学汇报自己的解题思路与方法。

1、填空题。

(1)360+482=( )+ 360 128+275=125+( )

(2)( )+ 78 =78 +149 133+( )=125+133

2、连线。

38+175 47+b

b+47 175+38

3、简便计算下面各题。

89+91+11 268+147+32

课堂小结:谈谈你有什么收获?有什么感受?还有问题吗?(学生总结不完整的地方,教师要适当补充总结)

(一)出示检测题(1—2题必做,3题选做,4题思考题)

1、根据加法交换律填空。

(1)450+320=( )+ 450 65+95=95+( )

(2)( )+ 100 =100+150 250+( )=125+( )

2、下面的哪些算式符合加法交换律。

(1)84 + c = b + 84

(2)10 + 20 + 30 + 40 =10 + (20 + 30) + 40

3、简便计算。

81+78+19 679+132+121

(二)堂清反馈:

作业布置

教材p30页习题。

板书设计

加法交换律

40+56=96(千米) 56+40 =96(千米)

a+b = b+a

苏教版加法交换律教学设计 加法交换律教学重点篇二

1、知识与技能:①结合具体的情境,引导学生认识和理解结合律的含义。

2、过程与方法:能用字母式子表示加法结合律,初步学会应用加法结合律进行一些简便运算。

3、情感态度与价值观:①体验自主探索、合作交流,感受成功的愉悦,树立学习数学的自信心,发展对数学的积极情感。②培养学生观察,比较,抽象,概括的初步思维能力。

认识和理解加法结合律的含义。

引导学生抽象,概括加法结合律。

多媒体课件。

一、自主学习

(一)出示自学提纲

自学提纲(p29页例2并完成自学提纲问题,将不会的问题做标注)

1、根据例2情境图中信息列出算式。

2、用你喜欢的方法尝试计算

3、同桌交流自己的算法

4、教师板书出学生的算式及答案

88+104+96 88+(104+96)

=192+96 =88+200

=288 =288

5、对比上面的两道算式,你发现了什么?用自己的话说一说。

(二)学生自学(学生对照自学提纲,自学教材p29页例2,并完成自学提纲问题,将不会的问题做标注)

(学生自学,教师在不干扰学生的前提下巡回指导,发现共性问题,以掌握学生学情)

(三)自学检测

1、填空

387+425=( )+ 387 525+( )=137+ 525

300+600=( )+( ) ( )+65=( )+35

2、连线

56+68 150+(25+75)

150+25+75 50+b

b+50 68+56

a+b+100 a+(b+100 )

三、合作探究

(一)小组互探(自学中遇到不会的问题,同桌或学习小组内互相交流。把小组也解决不了的问题记好,到学生质疑时提出,让其他学习小组或教师讲解。)

(引导学生正确地计算,鼓励学生分工合作,探索交流,教师巡回辅导,发现、收集学生存在的问题)

(二)师生互探

1、解答各小组自学中遇到不会的问题。

(1)让学生提出不会的问题,并让学生解决。

(2)教师引导学生解决学生还遗留的问题。

(3)如何用字母表示加法交换律和结合律?

(4)用字母表示这些运算定律有什么优点?

2、教师有针对性地请不同做法的同学汇报自己的解题思路与方法。

四、达标训练(1--3题必做,4题选做,5题思考题)

1、根据加法结合律填空题。

(1)78+25+22 =78 +( )+25

(2)376+175+25=376 +( + )

2、连线。

147+(72+28) a+(b+100 )

a+b+100 147+72+28

3、简便计算下面各题。

52+27+73 285+15+77+23

课堂小结:谈谈你有什么收获?有什么感受?还有问题吗?(学生总结不完整的地方,教师要适当补充总结)

五、堂清检测

(一)出示检测题

1、根椐加法的运算定律填空

(1)450+320=( )+ 450 65+95=95+( )

(2)( )+ 100 =100+150 250+( )=125+250

(3)78+25+22 =(78 + )+( )

(4)495+125+75=495 +( + )

2、下面的哪些算式符合加法结合律,哪些算式符合加法交换律。

(1)a + ( 30+9 )=a+ 30+9

(2)15+ ( 7+b )= (15 + 7 )+b

(3)10 + 20 + 30 + 40 =10 + (20 + 30) + 40

3、连线。

87+22+78 (79+83)+17

498+125+75 498+(125+75)

(138+136)+162 87+(22+78 )

79+(83+17) 138+136+162

4、简便计算。

98+72+28 215+85+73+27

(二)堂清反馈:

作业布置

苏教版加法交换律教学设计 加法交换律教学重点篇三

青岛版小学数学四年级下册第一单元信息窗三13页至14页的`内容。

1.让学生经历探索加法运算律的过程,理解并掌握加法交换律和结合律,会用字母来表示。

2.在探索运算律的过程中,发展学生的观察、比较、抽象、概括能力,培养学生的符号感。

3.让学生在数学学习过程中获得探究的乐趣、成功的喜悦,进一步增强对数学学习的兴趣和信心。

4.初步形成独立思考、合作交流的意识和习惯。

理解掌握加法的交换律和结合律,并会用字母表示他们。

引导学生通过讨论,计算从而自己发现并总结出加法交换律、加法结合律的过程。

课件、投影仪、卡片

一、拟定导学提纲,自主预习

(一)创设情境

1.谈话:同学们,长江,黄河就像两条长龙盘卧在中国大地,特别是黄河被称为我们的“母亲河”。这几天我们一直在学习有关黄河的知识,了解到了许多有关黄河的信息,除了我们学过的,你还了解到那些有关黄河的知识?(学生根据课前调查回答)想不想再多了解一些?

课件展示情境录像:(课件展示的关键是让学生从中知道黄河流域的小知识,例如上游:青藏高原黄土高原内蒙古高原中游:黄土高原下游:华北平原等小知识)最后大屏幕定格在信息窗三的情境图。

以上展示在大家面前的就是黄河流域图。教师板书:黄河流域

请同学们仔细观察,你能获得了哪些数学信息?

学生观察汇报,

生汇报:根据黄河流域图我了解到黄河分为上游、中游和下游(1、黄河上游长3472千米,中游长1206千米,下游长786千米;2、黄河上游流域面积是39万平方千米,中游是34万平方千米,下游是2万平方千米;)

教师适时板书相应的信息条件。

2.你能根据这些信息提出哪些数学问题呢?学生口答。教师板书出问题。

问题(1)黄河流域的面积是多少万平方千米?

问题(2)黄河全长多少千米?

(二)出示学习目标

同学们提出了这么多有价值的问题,那么今天我们将解决那些问题呢?请看本节课的学习目标:

1.让学生经历探索加法运算律的过程,理解并掌握加法交换律和结合律,会用字母来表示,能够运用所学的运算定律进行简算。

2.在探索运算律的过程中,发展学生的观察、比较、抽象、概括能力,培养学生的符号感。

(三)出示自学指导

为了能够更好地解决今天的学习目标,老师给大家提供了一些指导意见,请看自学指导。

(自学指导:请同学们认真看教科书第13—14页的信息窗3的第一个红点和小电脑的内容,重点看解决问题的过程,思考:(1)怎样解答同学们提出的问题?哪种方法简单?(2)什么是加法的结合律?怎样用字母式表示?(3)什么是加法交换律?怎样用字母式表示?

(5分钟后,比一比谁汇报得最清楚。)

(四)学生自学

师:下面请同学们根据“自学指导”开始自学,比一比谁看书最认真,谁自学效果最好!(师目光巡视每一个学生,特别要关注特困生。)

二、汇报交流,评价质疑

(一)调查

师:看完的同学请举手?

(二)全班汇报

1.问题一:黄河流域的面积是多少万平方千米?

学生在列式解答时,可能会出现两种情况

(1)39+34+2和34+2+39

(2)(39+34)+2和39+(34+2)。

2.问题二:黄河全长多少千米?

学生可能出的情况:

(1)、3470+1210+790和1210+790+3470

(2)(3470+1210)+790和3470+(1210+790)。

今天我们要学的知识就在这两组算式中。

(设计意图:充分运用教材情境图,引导学生获取信息,提出加法问题。在此基础上让学生列出算式。通过这两组算式学习今天的新知识,为下面学习埋下了伏笔。学生会马上把精力投入到这两个算式的研究中,激发了学生探究的兴趣。)

3.观察、比较、发现规律

(1)观察这些算式,你们发现了什么?

生汇报:每组算式运算的数相同,运算的结果相同,运算的顺序不同。

例如:

(39+34)+2=39+(34+2)

(3470+1210)+790=3470+(1210+790)。

(2)是不是所有的三个数相加都符合这些规律呢?举例验证一下吧:(每个学生在练习本上写出几组这样的算式,看结果怎样)

生汇报:

(35+63)+15=35+(63+15)

(325+82)+18=325+(82+18)…

(3)把你的发现告诉大家?(将学生的举例用实物投影展示)

(三个数相加时,先把前两个数相加,或先把后两个数相加,和不变。)

师指出这条规律叫做加法结合律。

(4)你能用你喜欢的方法表示这加法结合律吗?

学生用各种符号、字母表示这个运算定律。最终教师指出,在数学上,我们统一用a、b、c来表示三个加数,因此加法结合律可以写作(a+b)+c=a+(b+c)。学生齐读,教师板书在黑板上

小结:刚才我们通过解决两个问题发现并归纳出了加法结和律。

(设计意图:本环节经历了猜测—举例—验证—得出结论的过程,无形之中培养了学生一种数学思想。)

4.学法迁移,探索加法交换律。

那么,加法运算中还有其他的规律吗?想不想知道?我们先来做个游戏吧。

(1)游戏:找朋友。

在每个小组中都有一个算式卡片,请同学们小组合作,仔细想一想,算一算,它应该是屏幕上哪个算式的好朋友?为什么?

(2)同学们真棒,很快就为自己的算式找到了合适的朋友,还有谁的算式没有找到朋友?你能根据刚才同学们的方法给他介绍一个合适的好朋友吗?

苏教版加法交换律教学设计 加法交换律教学重点篇四

设计理念:生活经验是小学生学习数学的宝贵财富,也是他们进行数学探索的基础。教师应充分利用学生已有的生活经验,让他们在此基础上实现对数学的再创造,切实体验数学与生活的联系,经历数学知识发生、发展和形成的过程,提高学生应用数学解决实际问题的能力。

教材分析:教材从情境引出例题,帮助学生体会运算定律的现实背景,让学生借助解决实际问题,进一步体会和认识加法交换律,使学生经历由个别到一般,由具体到抽象的认知过程,引导学生由感性认识上升到一定的理性认识。

教学目标:探索和理解加法交换律,并能够用字母来表示加法交换律;经历探索运算定律过程,通过对实际问题的解决,进行比较和分析,发现并概括出加法交换律;在数学活动中获得成功的体验,培养学生独立思考和探究问题的意识和能力。

教学准备:多媒体课件。

教学过程:

1.导入故事《朝三暮四》,引发学生思考。根据学生回答板书:

3+4=7(个)4+3=7(个)3+4=4+3

2.创设问题情景。出示主题图,引导学生观察,图中告诉了我们哪些信息?我们要解决的问题是什么?

3.尝试解决问题。学生独立解决问题,根据学生解答板书:

40+56=96(千米)56+40=96(千米)40+56=56+40

引发猜想:是否任意两数相加,交换位置,和都不变?

1.交流:有了猜想,我们还得验证。你打算怎么验证?

2.学生举例验证,教师巡视指导。

1.同学们仔细观察列举出的等式,说一说你发现了什么?你能用自己的话说出你发现的规律,并给它命名吗?(两个加数交换位置,和不变。这叫加法交换律。)

2.让学生用自己喜欢的方式表示加法交换律。用语言表达加法交换律比较麻烦,怎样表示既简单又清楚呢?试一试,用你喜欢的符号、字母或图形表示两个加数。

1.引导学生由加法类比到减法、乘法和除法,并自觉形成关于减法、乘法和除法中是否有交换律的三个新猜想。

2.学生选择部分猜想,举例进行研究。教师参与,适时给予指导。

3.交流:哪一种猜想是正确的,你们是怎么举例验证得出结论的?教师板书若干例子,进而得出结论。

4.探讨:减法和除法中有交换律吗?学生交流后,引导思考:为什么只要举一个反例就能推翻猜想?

1.请同学们想一想,以前学过的知识中哪些地方用到过加法交换律?

2.下面我们就来比一比,看谁学得最好。

(1)你能在括号里填上合适的数吗?

300+600=()+()()+55=55+420 ()+65=()+35

(2)仔细看一看,下面的算式符合加法交换律吗?

270+380=380+270 b+800=800+b

(3)运用加法交换律,你能写出几个算式?写写试试吧。

25+49+75=()+()+()

学生写出算式以后,让学生观察这些算式,哪两个数交换了位置?在这些算式中,你认为哪一道计算起来比较简单?说说你的想法。

通过这节课的学习,你有哪些收获?说一说自己表现最好的方面。

(责任编辑付淑霞)

苏教版加法交换律教学设计 加法交换律教学重点篇五

教学目标

1、探索和理解加法交换律,并能灵活运用。

2、感受数学与现实生活的联系,并能用所学知识解决简单的实际问题。 教学重、难点

从现实的问题情景中抽象概括出加法交换律。

教学过程

一、诱趣激学

同学们喜欢看动画片吗?老师这里有一个小动画

1·动画片《朝三暮四》

2·引发思考,感知规律

看完这个动画片,你想对同学们说些什么?(如果学生们笑了,就借机问问学生们笑什么?)引导说出:

4+3=7(个) 3+4=7(个)课件出示

问:这两个算式有什么联系?(得数都等于7,都表示猴子一天吃的桃子)。这两个算式之间可以用什么数学符号连接起来呢?(等号)

课件演示:4+3=3+4

二、自主探究,寻找规律

1.解决问题,发现规律

谈话:其实这样的数学问题就在我们身边,同学们会骑自行吗?(会),李叔叔也会骑车,他这里有一个问题需要我们帮忙解决一下。 课件出示骑车主题图。

问:从中你可以得到哪些信息?要求什么呢?(上午骑了40千米,下午骑了56千米,今天一共骑了多少千米?)

问:一共骑了多少千米?能列式计算解决这个问题吗?(能)

请在草稿本上做,老师下去找到需要的答案,板书黑板。

40+56=96(千米)56+40=96(千米)

问:观察这两个同学的列式,你们发现呢什么?

两个算式计算的结果都是一样的,我们可以用等号连接起来。

课件出示40+56=96(千米)56+40=96(千米)

40+56=56+40

2.举例猜想,概括规律

课件出示4+3=3+440+56=56+40

观察这两组算式,都是两边计算的结果相等,可以用等号连接,你能再举出几个这样的列子吗?同桌互相交流。

全班交流,把学生的汇报结果写在黑板上。

同学们真聪明,举了这么多的列子,你能发现什么规律吗?请用最简洁的话概括出来。 同桌交流。

全班交流,总结板书:两个加数交换位置,和不变。

问:你能给这个规律起个名字吗?(加法交换律)

我把加数换成其他任意的数,交换律还成立吗?老师这里有几组算式 课件出示讲解过程

① 30+20 两位数加上两位数,交换加数的位置,和是不变

② 100+30 三位数加上两位数,交换加数的位置,和也是不变

③ 1000+200 四位数加上三位数,交换加数的位置,和还是不变

刚才经过同学们的努力,我们发现了不管这两个加数是什么,只要两个加数交换了位置,他们的和不变。我们把这个规律叫做加法交换律。(板书:加法交换律)课件出示加法交换律的内容。

3.用喜欢的方式表示规律

怎样表示任意两数相加,交换加数位置和不变呢?你能用自己喜欢的方式表示吗?

请同学们相互讨论,老师下去帮助同学

全班交流 想法一:甲数+乙数=乙数+甲数

想法二:□+○=○+□

想法三:a+b=b+a

师:同学们各抒己见,用了这么多的方式表示。同学们觉得哪一种最好呢?为什么?(简洁明了。)

课件出示:a+b=b+a

谈话:咱们知道了加法交换律,并且会用自己喜欢的方式表示,请同学们想一想,以前学过的知识中,哪些地方用到过加法交换律(验算加法时)

课件演示876+1924

4.思考题,拓展规律

下面这个等式应用了加法交换律吗?

课件出示3+4+5=4+3+5

在三个数相加里面,我们也可以用加法交换律

运用加法交换律,在括号里填上适当的数

355+423=423+()

258+( ) =340+()

a+268=268+( )

35+42+65=35+()+( )

总结:这节课上,同学们个个表现都很棒,积极思考,踊跃回答问题,学习热情不断高涨,数学家们总结的规律,我们也能发现,同学们真棒,想一想我们探索加法交换律的过程,你有什么收获呢?

苏教版加法交换律教学设计 加法交换律教学重点篇六

教学目标

1、让学生在经历探索加法交换律和加法结合律的过程中,理解并掌握加法交换律和加法结合律,初步感受到应用加法运算律可以使一些计算简便。

2、在探索运算律的过程中,发展学生的分析、比较、抽象、概括能力 ,培养学生的符号感。

3、让学生在数学活动中获得成功的体验,进一步增强对数学学习的兴趣和信心,初步形成独立思考和探究问题的意识和习惯。

教学重点

理解加法的运算律。

教学难点

概括加法的运算律,尝试用字母表示。

教学过程

二、教学加法交律。

1、课件出示:这是同学们课外活动的情况。谁能来解决这个问题?根据学生回答,联系题意讲解,并板书:28+17=45(人),问:还可能怎样想:17+28=45(人)。

板书算式。

2、比较这两道算式有什么不同?

3、得数相同的算式我们可以用等号把它们连成等式。

4、举例:你能再说出几个这样的等式吗?自己写一写。学生说,老师相机板书等式,并追问:介绍一下你是怎么写的?核实是否相等。

5、概括规律:仔细观察,有什么规律?根据学生回答,相机引导发现规律。

6、用自己喜欢的方式表示这个规律?可适当提示:用符号、文字、字母

学生思考,充分发表自己意见,教师给予肯定。

7、数学上,我们一般用a、b表示两个加数,可以写成:a+b=b+a.老师小结:

引出:加法交换律(板书)

8、小练习:填数

1、过渡:刚才我们一起动脑,有了很多发现,大家真不简单。现在我们再来解决一个问题,看看会有哪些收获?课件出示

2、列式解答,利用题意追问算式含义,并相机加括号表示先算。还可能先算什么?说算式含义

3、比较这两个算式:有什么不同?什么相同?得数为什么相同?我们可以用等号连成等式。

4、出示书上题目,说一说,算一算。

5、概括规律:仔细观察,你有什么发现?学生回答,教师引导发现规律。

6、你能不能再举几个例子?学生举例。

7、教师小结,引出:加法结合律(板书)。如果用a、b、c分别表示这三个加数,加法结合律可以表示成?

8、小练习:填数。

1、刚才我们学习了加法交换律和加法结合律,它们都是运用在加法中的规律。师总结。

2、课后练习:

(1)下面等式各应用了什么运算律?学生说一说,对第三道重点分析,引出加法运算律有作用

(2)比较体会运算律的作用,知道凑整百。

(3)凑整百小练习。

苏教版加法交换律教学设计 加法交换律教学重点篇七

������ñ§ï¿½ï¿½ï¿½ï¿½

�����ì²ï¿½p28ò³ï¿½ï¿½1��p30ò³ï¿½ï¿½ï°ï¿½ï¿½ï¿½ï°ï¿½â¡£

������ñ§ä¿ï¿½ï¿½

����1��öªê¶ï¿½ë¼¼ï¿½ü£ï¿½

������ï¾ï¿½ï¿½ï¿½ï¿½ï¿½é¾³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµäºï¿½ï¿½å¡£

����2�������뷽����������ä¸ê½ï¿½ó±ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ó¦ï¿½ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é½ï¿½ï¿½ï¿½ò»ð©ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¡£

����3�����ì¬ï¿½ï¿½ï¿½ï¿½ï¿½öµï¿½û£ï¿½

��������������ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ü³é¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä£ï¿½ï¿½ï¿½õ¹ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ä»ï¿½ï¿½ï¿½ï¿½ï¿½ð¡ï¿½

����������ñ§ï¿½ï¿½ï¿½û²ì£¬ï¿½è½ï£ï¿½ï¿½ï¿½ï¿½ó£¬¸ï¿½ï¿½ï¿½ï¿½ä³ï¿½ï¿½ï¿½ë¼î¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������ñ§ï¿½øµï¿½

������ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµäºï¿½ï¿½å¡£

������ñ§ï¿½ñµï¿½

��������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ó£¬¸ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������ñ§ï¿½ã¾ï¿½

������ã½ï¿½ï¿½î¼ï¿½ï¿½ï¿½

������ñ§ï¿½ï¿½ï¿½ï¿½

����

������ò»ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ñ§ï¿½ï¿½ï¿½

������ñ§ï¿½ï¿½ù£ï¿½ï¿½ì²ï¿½p28ò³ï¿½ï¿½1���������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½×¢ï¿½ï¿½

����1��������1�龳í¼ï¿½ï¿½ï¿½ï¿½ï¢ï¿½ð³ï¿½ï¿½ï¿½ê½ï¿½ï¿½

����2������ï²ï¿½ï¿½ï¿½ä·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ï¿½

����3��í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ï¿½ï¿½ã·¨

����4����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½

����40+56=96��ç§ï¿½×£ï¿½ 56+40=96��ç§ï¿½×£ï¿½

����5���ô±ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ã·¢ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ä»ï¿½ëµò»ëµï¿½ï¿½

����������ñ§ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ù£ï¿½ï¿½ï¿½ñ§ï¿½ì²ï¿½p28ò³ï¿½ï¿½1���������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½×¢ï¿½ï¿½

������ñ§ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ú²ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ç°ï¿½ï¿½ï¿½ï¿½ñ²ï¿½ï¿½ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ñ§ï¿½é£©

������������ñ§ï¿½ï¿½ï¿½

����1�����

����387+425=�� ��+ 387 525+�� ��=137+ 525

����300+600=�� ��+�� �� �� ��+65=�� ��+35

��������+����=�� ��+�� �� å¼ï¿½ï¿½+�� ��=����+�� ��

����2������

����56+68 50+b

����b+50 68+56

����

������ò»ï¿½ï¿½ð¡ï¿½é»¥ì½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬í¬ï¿½ï¿½ï¿½ï¿½ñ§ï°ð¡ï¿½ï¿½ï¿½ú»ï¿½ï¿½à½»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¡ï¿½ï¿½ò²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ëµï¿½ï¿½ï¿½ï¿½ï¿½çºã£ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê±ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ð¡ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½â¡£ï¿½ï¿½

����������ñ§ï¿½ï¿½ï¿½ï¿½è·ï¿½ø¼ï¿½ï¿½ã£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ö¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ñ²ï¿½ø¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¡ï¿½ï¿½õ¼ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½úµï¿½ï¿½ï¿½ï¿½â£©

����������ê¦ï¿½ï¿½ï¿½ï¿½ì½

����1������ð¡ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

������1����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������2����ê¦ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

������3���������ä¸ï¿½ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí½ï¿½ï¿½ï¿½é£ï¿½

������4������ä¸ï¿½ï¿½ê¾ï¿½ï¿½ð©ï¿½ï¿½ï¿½ã¶¨ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½åµã£¿

����2����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ôµï¿½ï¿½ë²»í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ã±¨ï¿½ô¼ï¿½ï¿½ä½ï¿½ï¿½ï¿½ë¼â·ï¿½ë·½ï¿½ï¿½ï¿½ï¿½

����

����1������⡣

������1��360+482=�� ��+ 360 128+275=125+�� ��

������2���� ��+ 78 =78 +149 133+�� ��=125+133

����2�����ߡ�

����38+175 47+b

����b+47 175+38

����3��������������⡣

����89+91+11 268+147+32

��������ð¡ï¿½á£ºì¸ì¸ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½õ»ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ü£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ñ§ï¿½ï¿½ï¿½ü½á²»ï¿½ï¿½ï¿½ï¿½ï¿½äµø·ï¿½ï¿½ï¿½ï¿½ï¿½ê¦òªï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ü½á£©

����

������ò»ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½â£¨1��2�������3��ñ¡ï¿½ï¿½ï¿½ï¿½4��ë¼ï¿½ï¿½ï¿½â£©

����1�����ý¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½õ¡ï¿½

������1��450+320=�� ��+ 450 65+95=95+�� ��

������2���� ��+ 100 =100+150 250+�� ��=125+�� ��

����2���������ð©ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������1��84 + c = b + 84

������2��10 + 20 + 30 + 40 =10 + (20 + 30) + 40

����3�������㡣

����81+78+19 679+132+121

�������������巴����

������òµï¿½ï¿½ï¿½ï¿½

�����ì²ï¿½p30ò³ï°ï¿½â¡£

�����������

�����ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����40+56=96��ç§ï¿½×£ï¿½ 56+40 =96��ç§ï¿½×£ï¿½

����a+b = b+a

苏教版加法交换律教学设计 加法交换律教学重点篇八

����

�����ൺ��ð¡ñ§ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ê¼¶ï¿½â²ï¿½ï¿½ò»ï¿½ï¿½ôªï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½13ò³ï¿½ï¿½14ò³ï¿½ï¿½`���ý¡ï¿½

����

����1����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½â²¢ï¿½ï¿½ï¿½õ¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½

����2����ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ï¿½ï¿½ð£ï¿½ï¿½ï¿½õ¹ñ§ï¿½ï¿½ï¿½ä¹û²ì¡¢ï¿½è½ï¡ï¿½ï¿½ï¿½ï¿½ó¡¢¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ä·ï¿½ï¿½å¸ð¡ï¿½

����3.��ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ñ§ï°ï¿½ï¿½ï¿½ï¿½ï¿½ð»ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½è¤ï¿½ï¿½ï¿½é¹ï¿½ï¿½ï¿½ï²ï¿½ã£ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ç¿ï¿½ï¿½ï¿½ï¿½ñ§ñ§ï°ï¿½ï¿½ï¿½ï¿½è¤ï¿½ï¿½ï¿½ï¿½ï¿½ä¡ï¿½

����4.�����î³é¶ï¿½ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï°ï¿½ß¡ï¿½

����

�����������õ¼ó·ï¿½ï¿½ä½ï¿½ï¿½ï¿½ï¿½éºí½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ç¡ï¿½

����

��������ñ§ï¿½ï¿½í¨ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½,����ó¶ï¿½ï¿½ô¼ï¿½ï¿½ï¿½ï¿½ö²ï¿½ï¿½ü½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ì¡ï¿½

����

�����î¼ï¿½ï¿½ï¿½í¶ó°ï¿½ç¡ï¿½ï¿½ï¿½æ¬

����

����ò»ï¿½ï¿½ï¿½â¶¨ï¿½ï¿½ñ§ï¿½ï¿½ù£ï¿½ï¿½ï¿½ï¿½ï¿½ô¤ï°

������ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¾³

����1��ì¸ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ç£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½æºó¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¹ï¿½ï¿½ï¿½ø£ï¿½ï¿½ø±ï¿½ï¿½ç»æºó±ï¿½ï¿½ï¿½îªï¿½ï¿½ï¿½çµä¡ï¿½ä¸ï¿½×ºó¡ï¿½ï¿½ï¿½ï¿½â¼¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ö±ï¿½ï¿½ñ§ï°ï¿½ð¹ø»æºóµï¿½öªê¶ï¿½ï¿½ï¿½ë½âµ½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¹ø»æºóµï¿½ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ä£ï¿½ï¿½ã»¹ï¿½ë½âµ½ï¿½ï¿½ð©ï¿½ð¹ø»æºóµï¿½öªê¶ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ý¿ï¿½ç°ï¿½ï¿½ï¿½ï¿½ø´ï¿½ï¿½ë²»ï¿½ï¿½ï¿½ù¶ï¿½ï¿½ë½ï¿½ò»ð©ï¿½ï¿½

�����î¼ï¿½õ¹ê¾ï¿½é¾³â¼ï¿½ñ£º£ï¿½ï¿½î¼ï¿½õ¹ê¾ï¿½ä¹ø¼ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½öªï¿½ï¿½ï¿½æºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¡öªê¶,�������î£ï¿½ï¿½ï¿½ø¸ï¿½ô­ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô­ï¿½ï¿½ï¿½é¹å¸ï¿½ô­ï¿½ï¿½ï¿½î£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô­ï¿½ï¿½ï¿½î£ï¿½ï¿½ï¿½ï¿½ï¿½æ½ô­ï¿½ï¿½ð¡öªê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¾³í¼ï¿½ï¿½

��������õ¹ê¾ï¿½ú´ï¿½ï¿½ï¿½ï¿½ç°ï¿½ä¾ï¿½ï¿½ç»æºï¿½ï¿½ï¿½ï¿½ï¿½í¼ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½é£ºï¿½æºï¿½ï¿½ï¿½ï¿½ï¿½

������í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¸ï¿½û²ì£¬ï¿½ï¿½ï¿½ü»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ñ§ï¿½ï¿½ï¢ï¿½ï¿½

����ñ§ï¿½ï¿½ï¿½û²ï¿½ã±¨ï¿½ï¿½

�������㱨�����ý»æºï¿½ï¿½ï¿½ï¿½ï¿½í¼ï¿½ï¿½ï¿½ë½âµ½ï¿½æºó·ï¿½îªï¿½ï¿½ï¿½î¡ï¿½ï¿½ï¿½ï¿½îºï¿½ï¿½ï¿½ï¿½î£ï¿½1���æºï¿½ï¿½ï¿½ï¿½î³ï¿½3472ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½î³ï¿½1206ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½î³ï¿½786ç§ï¿½×£ï¿½2���æºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½39��æ½ï¿½ï¿½ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½34��æ½ï¿½ï¿½ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½2��æ½ï¿½ï¿½ç§ï¿½×£ï¿½ï¿½ï¿½

������ê¦ï¿½ï¿½ê±ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó¦ï¿½ï¿½ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����2�����ü¸ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ø£ï¿½ñ§ï¿½ï¿½ï¿½ú´ð¡£½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

�������⣨1���æºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç¶ï¿½ï¿½ï¿½ï¿½ï¿½æ½ï¿½ï¿½ç§ï¿½×£ï¿½

�������⣨2���æºï¿½è«ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç§ï¿½×£ï¿½

������������ê¾ñ§ï°ä¿ï¿½ï¿½

����í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ï¿½ï¿½ï¿½ð¼ï¿½öµï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ï¿½ï¿½ï¿½ø£ï¿½ï¿½ë¿´ï¿½ï¿½ï¿½ú¿îµï¿½ñ§ï°ä¿ï¿½ê£º

����1����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½â²¢ï¿½ï¿½ï¿½õ¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ü¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ã¶¨ï¿½é½ï¿½ï¿½ð¼ï¿½ï¿½ã¡£

����2����ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ï¿½ï¿½ð£ï¿½ï¿½ï¿½õ¹ñ§ï¿½ï¿½ï¿½ä¹û²ì¡¢ï¿½è½ï¡ï¿½ï¿½ï¿½ï¿½ó¡¢¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ä·ï¿½ï¿½å¸ð¡ï¿½

������������ê¾ï¿½ï¿½ñ§ö¸ï¿½ï¿½

����îªï¿½ï¿½ï¿½ü¹ï¿½ï¿½ï¿½ï¿½ãµø½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ä¿ï¿½ê£¬ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½á¹©ï¿½ï¿½ò»ð©ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¿´ï¿½ï¿½ñ§ö¸ï¿½ï¿½ï¿½ï¿½

��������ñ§ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½æ¿´ï¿½ì¿ï¿½ï¿½ï¿½ï¿½13��14ò³ï¿½ï¿½ï¿½ï¿½ï¢ï¿½ï¿½3�äµï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¡ï¿½ï¿½ï¿½ôµï¿½ï¿½ï¿½ï¿½ý£ï¿½ï¿½øµã¿´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¹ï¿½ï¿½ì£ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½1���������í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¿ï¿½ï¿½ï¿½ö·ï¿½ï¿½ï¿½ï¿½òµ¥£ï¿½ï¿½ï¿½2��ê²ã´ï¿½ç¼ó·ï¿½ï¿½ä½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ê½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½3��ê²ã´ï¿½ç¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ê½ï¿½ï¿½ê¾ï¿½ï¿½

������5���óºó£¬±ï¿½ò»ï¿½ï¿½ë­ï¿½ã±¨ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�������ä£ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ñ§

����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ç¸ï¿½ï¿½ý¡ï¿½ï¿½ï¿½ñ§ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¼ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ë­ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½æ£¬ë­ï¿½ï¿½ñ§ð§ï¿½ï¿½ï¿½ï¿½ã£ï¿½ï¿½ï¿½ê¦ä¿ï¿½ï¿½ñ²ï¿½ï¿½ã¿ò»ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ø±ï¿½òªï¿½ï¿½×¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

���������㱨��������������

������ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ï¿½ï¿½ö£ï¿½

����������è«ï¿½ï¿½ã±¨

����1������ò»ï¿½ï¿½ï¿½æºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç¶ï¿½ï¿½ï¿½ï¿½ï¿½æ½ï¿½ï¿½ç§ï¿½×£ï¿½

����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ê±ï¿½ï¿½ï¿½ï¿½ï¿½ü»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������1��39��34��2��34��2��39

������2����39��34����2��39����34��2����

����2����������æºï¿½è«ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç§ï¿½×£ï¿½

����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ü³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������1����3470+1210+790��1210+790+3470

������2����3470+1210��+790��3470+��1210+790����

������������òªñ§ï¿½ï¿½öªê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ð¡ï¿½

�����������í¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã½ì²ï¿½ï¿½é¾³í¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½è¡ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½â¡£ï¿½ú´ë»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ð³ï¿½ï¿½ï¿½ê½ï¿½ï¿½í¨ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ñ§ï°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½öªê¶ï¿½ï¿½îªï¿½ï¿½ï¿½ï¿½ñ§ï°ï¿½ï¿½ï¿½ï¿½ï¿½ë·ï¿½ï¿½ê¡ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï°ñ¾ï¿½ï¿½ï¿½í¶ï¿½ëµ½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ð¾ï¿½ï¿½ð£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½è¤ï¿½ï¿½ï¿½ï¿½

����3���û²ì¡¢ï¿½è½ï¡ï¿½ï¿½ï¿½ï¿½ö¹ï¿½ï¿½ï¿½

������1���û²ï¿½ï¿½ï¿½ð©ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ç·ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½

�������㱨��ã¿ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä½ï¿½ï¿½ï¿½ï¿½í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë³ï¿½ï¿½í¬ï¿½ï¿½

�������磺

������39��34����2��39����34��2��

������3470+1210��+790��3470+��1210+790����

������2���ç²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ðµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ï¿½ï¿½ï¿½ø£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¤ò»ï¿½â°é£ï¿½ï¿½ï¿½ã¿ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï°ï¿½ï¿½ï¿½ï¿½ð´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�������㱨��

������35+63��+15=35+��63+15��

������325+82��+18=325+��82+18����

������3������ä·ï¿½ï¿½ö¸ï¿½ï¿½ß´ï¿½ò£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ä¾ï¿½ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½í¶ó°õ¹ê¾ï¿½ï¿½

���������������ê±ï¿½ï¿½ï¿½è°ï¿½ç°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½è°ñºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½í²ï¿½ï¿½ä¡£ï¿½ï¿½

����ê¦ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������4����������ï²ï¿½ï¿½ï¿½ä·ï¿½ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����ñ§ï¿½ï¿½ï¿½ã¸ï¿½ï¿½ö·ï¿½ï¿½å¡ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¶¨ï¿½é¡ï¿½ï¿½ï¿½ï¿½õ½ï¿½ê¦ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï£ï¿½ï¿½ï¿½ï¿½ï¿½í³ò»ï¿½ï¿½a��b��c����ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é¿ï¿½ï¿½ï¿½ð´ï¿½ï¿½ï¿½ï¿½a+b��+c=a+��b+c����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½úºú°ï¿½ï¿½ï¿½

����ð¡ï¿½á£ºï¿½õ²ï¿½ï¿½ï¿½ï¿½ï¿½í¨ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â·¢ï¿½ö²ï¿½ï¿½ï¿½ï¿½é³ï¿½ï¿½ë¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

�����������í¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ú¾ï¿½ï¿½ï¿½ï¿½ë²â²â¡ªï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¤ï¿½ï¿½ï¿½ã³ï¿½ï¿½ï¿½ï¿½ûµä¹ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½ï¿½ö®ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ñ§ë¼ï¿½ë¡£ï¿½ï¿½

����4��ñ§ï¿½ï¿½ç¨ï¿½æ£ï¿½ì½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������ã´ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë²»ï¿½ï¿½öªï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï·ï¿½é¡ï¿½

����(1)��ï·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ¡ï¿½

������ã¿ï¿½ï¿½ð¡ï¿½ï¿½ï¿½ð¶ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½æ¬ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ð¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¸ï¿½ï¿½ò»ï¿½ë£¬ï¿½ï¿½ò»ï¿½ã£¬ï¿½ï¿½ó¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä»ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ï¿½ê½ï¿½äºï¿½ï¿½ï¿½ï¿½ñ£ï¿½îªê²ã´ï¿½ï¿½

������2��í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ü¿ï¿½ï¿½îªï¿½ô¼ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½òµï¿½ï¿½ëºï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ñ£ï¿½ï¿½ï¿½ï¿½ï¿½ë­ï¿½ï¿½ï¿½ï¿½ê½ã»ï¿½ï¿½ï¿½òµï¿½ï¿½ï¿½ï¿½ñ£ï¿½ï¿½ï¿½ï¿½ü¸ï¿½ï¿½ý¸õ²ï¿½í¬ñ§ï¿½çµä·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½êµäºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

苏教版加法交换律教学设计 加法交换律教学重点篇九

������ñ§ä¿ï¿½ï¿½

����1����ñ§ï¿½ï¿½ï¿½ú¾ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ï¿½ï¿½ð£ï¿½ï¿½ï¿½ï¿½â²¢ï¿½ï¿½ï¿½õ¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½üµï¿½ó¦ï¿½ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¿ï¿½ï¿½ï¿½ê¹ò»ð©ï¿½ï¿½ï¿½ï¿½ï¿½ã¡£

����2����ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ï¿½ï¿½ð£ï¿½ï¿½ï¿½õ¹ñ§ï¿½ï¿½ï¿½ä·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½è½ï¡ï¿½ï¿½ï¿½ï¿½ó¡¢¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ������ñ§ï¿½ï¿½ï¿½ä·ï¿½ï¿½å¸ð¡ï¿½

����3����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½î¶¯ï¿½ð»ï¿½ã³é¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£¬ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ç¿ï¿½ï¿½ï¿½ï¿½ñ§ñ§ï°ï¿½ï¿½ï¿½ï¿½è¤ï¿½ï¿½ï¿½ï¿½ï¿½ä£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î³é¶ï¿½ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï°ï¿½ß¡ï¿½

������ñ§ï¿½øµï¿½

��������ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������ñ§ï¿½ñµï¿½

���������ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ê¾ï¿½ï¿½

������ñ§ï¿½ï¿½ï¿½ï¿½

����������ñ§ï¿½ó·ï¿½ï¿½ï¿½ï¿½é¡ï¿½

����1���î¼ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ç¿ï¿½ï¿½ï¿½î¶¯ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë­ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¿ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ø´ï¿½ï¿½ï¿½ïµï¿½ï¿½ï¿½â½²ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½é£º28+17=45���ë£ï¿½ï¿½ï¿½ï¿½ê£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë£º17+28=45���ë£ï¿½ï¿½ï¿½

����������ê½ï¿½ï¿½

����2���è½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ê²ã´ï¿½ï¿½í¬ï¿½ï¿½

����3��������í¬ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ç¿ï¿½ï¿½ï¿½ï¿½ãµèºå°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµï¿½ê½ï¿½ï¿½

����4��������������ëµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½äµï¿½ê½ï¿½ï¿½ï¿½ô¼ï¿½ð´ò»ð´ï¿½ï¿½ñ§ï¿½ï¿½ëµï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½×·ï¿½ê£ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ð´ï¿½ä£ï¿½ï¿½ï¿½êµï¿½ç·ï¿½ï¿½ï¿½è¡ï¿½

����5���������é£ï¿½ï¿½ï¿½ï¸ï¿½û²ì£¬ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ø´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¹ï¿½ï¿½é¡ï¿½

����6�����ô¼ï¿½ï²ï¿½ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ã·ï¿½ï¿½å¡ï¿½ï¿½ï¿½ï¿½ö¡ï¿½ï¿½ï¿½ä¸

����ñ§ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö·ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¶ï¿½ï¿½ï¿½

����7����ñ§ï¿½ï£ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½a��b��ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð´ï¿½é£ï¿½a+b=b+a.��ê¦ð¡ï¿½á£º

�����������ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½é£©

����8��ð¡ï¿½ï¿½ï°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����1�����é£ï¿½ï¿½õ²ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ô£ï¿½ï¿½ï¿½ï¿½ëºü¶à·¢ï¿½ö£ï¿½ï¿½ï¿½ï¿½ï¿½æ²»ï¿½òµ¥¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½õ»ñ£¿¿î¼ï¿½ï¿½ï¿½ê¾

����2����ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½×·ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½å£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½å±ï¿½ê¾ï¿½ï¿½ï¿½ã¡£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ëµï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½

����3���è½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½í¬ï¿½ï¿½ê²ã´ï¿½ï¿½í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½îªê²ã´ï¿½ï¿½í¬ï¿½ï¿½ï¿½ï¿½ï¿½ç¿ï¿½ï¿½ï¿½ï¿½ãµèºï¿½ï¿½ï¿½ï¿½éµï¿½ê½ï¿½ï¿½

����4����ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä¿ï¿½ï¿½ëµò»ëµï¿½ï¿½ï¿½ï¿½ò»ï¿½ã¡£

����5���������é£ï¿½ï¿½ï¿½ï¸ï¿½û²ì£¬ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ö£ï¿½ñ§ï¿½ï¿½ï¿½ø´ð£¬½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¹ï¿½ï¿½é¡ï¿½

����6�����ü²ï¿½ï¿½ï¿½ï¿½ù¾ù¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����7����ê¦ð¡ï¿½á£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½é£©ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½a��b��c�ö±ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½é¿ï¿½ï¿½ô±ï¿½ê¾ï¿½é£ï¿½

����8��ð¡ï¿½ï¿½ï°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����1���õ²ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ï¿½ë¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ç¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ú¼ó·ï¿½ï¿½ðµä¹ï¿½ï¿½é¡ï¿½ê¦ï¿½ü½á¡£

����2���îºï¿½ï¿½ï¿½ï°ï¿½ï¿½

������1�������ê½ï¿½ï¿½ó¦ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ñ§ï¿½ï¿½ëµò»ëµï¿½ï¿½ï¿½ôµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½øµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¡ï¿½

������2���è½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµï¿½ï¿½ï¿½ï¿½ã£ï¿½öªï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ù¡ï¿½

������3��������ð¡ï¿½ï¿½ï°ï¿½ï¿½

苏教版加法交换律教学设计 加法交换律教学重点篇十

������ñ§ä¿ï¿½ï¿½

����1��ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¡ï¿½

����2��������ñ§ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ïµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§öªê¶ï¿½ï¿½ï¿½ï¿½òµ¥µï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½â¡£ ��ñ§ï¿½ø¡ï¿½ï¿½ñµï¿½

��������êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¾°ï¿½ð³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������ñ§ï¿½ï¿½ï¿½ï¿½

����ò»ï¿½ï¿½ï¿½ï¿½è¤ï¿½ï¿½ñ§

����í¬ñ§ï¿½ï¿½ï²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½æ¬ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ð¡ï¿½ï¿½ï¿½ï¿½

����1������æ¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½äºï¿½ä¡ï¿½

����2������ë¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½öªï¿½ï¿½ï¿½ï¿½

���������������æ¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ëµð©ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ð¦ï¿½ë£ï¿½ï¿½í½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ð¦ê²ã´?������ëµï¿½ï¿½ï¿½ï¿½

����4+3=7������ 3+4=7�������î¼ï¿½ï¿½ï¿½ê¾

�����ê£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ê²ã´ï¿½ï¿½ïµ?(����������7������ê¾ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ôµï¿½ï¿½ï¿½ï¿½ï¿½)����������ê½ö®ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ø£ï¿½ï¿½ï¿½ï¿½èºå£ï¿½

�����î¼ï¿½ï¿½ï¿½ê¾ï¿½ï¿½4+3=3+4

������������ì½ï¿½ï¿½ï¿½ï¿½ñ°ï¿½ò¹ï¿½ï¿½ï¿½

����1.������⣬���ö¹ï¿½ï¿½ï¿½

����ì¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ß£ï¿½í¬ñ§ï¿½ç»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ï¿½á£©ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò²ï¿½ï¿½ï¿½ï³µï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½òªï¿½ï¿½ï¿½ç°ï¿½ã¦ï¿½ï¿½ï¿½ò»ï¿½â¡ï¿½ �î¼ï¿½ï¿½ï¿½ê¾ï¿½ï³µï¿½ï¿½ï¿½ï¿½í¼ï¿½ï¿½

�����ê£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ôµãµï¿½ï¿½ï¿½ð©ï¿½ï¿½ï¢ï¿½ï¿½òªï¿½ï¿½ê²ã´ï¿½ø£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½40ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½56ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ë¶ï¿½ï¿½ï¿½ç§ï¿½×£ï¿½ï¿½ï¿½

�����ê£ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ë¶ï¿½ï¿½ï¿½ç§ï¿½×£ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ï¿½ü£ï¿½

�������ú²ý¸å±¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½è¥ï¿½òµï¿½ï¿½ï¿½òªï¿½ä´ð°¸£ï¿½ï¿½ï¿½ï¿½ï¿½ú°å¡£

����40+56=96��ç§ï¿½×£ï¿½56+40=96��ç§ï¿½×£ï¿½

�����ê£ï¿½ï¿½û²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ç·ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½

����������ê½ï¿½ï¿½ï¿½ï¿½ä½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ä£ï¿½ï¿½ï¿½ï¿½ç¿ï¿½ï¿½ï¿½ï¿½ãµèºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�����î¼ï¿½ï¿½ï¿½ê¾40+56=96��ç§ï¿½×£ï¿½56+40=96��ç§ï¿½×£ï¿½

����40+56=56+40

����2.�������룬��������

�����î¼ï¿½ï¿½ï¿½ê¾4+3=3+440+56=56+40

�����û²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ß¼ï¿½ï¿½ï¿½ä½ï¿½ï¿½ï¿½ï¿½è£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ãµèºï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ù¾ù³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ï¿½ï¿½ï¿½ï¿½ï¿½à½»ï¿½ï¿½ï¿½ï¿½

����è«ï¿½à½»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ä»ã±¨ï¿½ï¿½ï¿½ð´ï¿½úºú°ï¿½ï¿½ï¡ï¿½

����í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½ü·ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����è«ï¿½à½»ï¿½ï¿½ï¿½ï¿½ï¿½ü½ï¿½ï¿½ï¿½é£ºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½í²ï¿½ï¿½ä¡£

�����ê£ï¿½ï¿½ï¿½ï¿½ü¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½

�����ò°ñ¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ð¼ï¿½ï¿½ï¿½ï¿½ï¿½ê½ �î¼ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������ 30+20 ��î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½ï¿½ï¿½ç²ï¿½ï¿½ï¿½

������ 100+30 ��î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½ï¿½ò²ï¿½ç²ï¿½ï¿½ï¿½

������ 1000+200 ��î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½í»ï¿½ï¿½ç²ï¿½ï¿½ï¿½

�����õ²å¾ï¿½ï¿½ï¿½í¬ñ§ï¿½çµï¿½å¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç·ï¿½ï¿½ï¿½ï¿½ë²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ö»òªï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½ï¿½ï¿½çµäºí²ï¿½ï¿½ä¡£ï¿½ï¿½ï¿½ç°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ºï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½î¼ï¿½ï¿½ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµï¿½ï¿½ï¿½ï¿½ý¡ï¿½

����3.��ï²ï¿½ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½

����������ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ãºí²ï¿½ï¿½ï¿½ï¿½ø£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï²ï¿½ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ï¿½

������í¬ñ§ï¿½ï¿½ï¿½à»¥ï¿½ï¿½ï¿½û£ï¿½ï¿½ï¿½ê¦ï¿½ï¿½è¥ï¿½ï¿½ï¿½ï¿½í¬ñ§

����è«ï¿½à½»ï¿½ï¿½ �뷨ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½+����=����+����

�����뷨������+��=��+��

�����뷨����a+b=b+a

����ê¦ï¿½ï¿½í¬ñ§ï¿½ç¸ï¿½ï¿½ã¼ºï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ï¿½í¬ñ§ï¿½ç¾ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½?îªê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¡ï¿½ï¿½ï¿½

�����î¼ï¿½ï¿½ï¿½ê¾ï¿½ï¿½a+b=b+a

����ì¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½öªï¿½ï¿½ï¿½ë¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï²ï¿½ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ï¿½ï¿½ï¿½ò»ï¿½ë£¬ï¿½ï¿½ç°ñ§ï¿½ï¿½ï¿½ï¿½öªê¶ï¿½ð£ï¿½ï¿½ï¿½ð©ï¿½ø·ï¿½ï¿½ãµï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ê±ï¿½ï¿½

�����î¼ï¿½ï¿½ï¿½ê¾876+1924

����4.ë¼ï¿½ï¿½ï¿½â£¬ï¿½ï¿½õ¹ï¿½ï¿½ï¿½ï¿½

�������������ê½ó¦ï¿½ï¿½ï¿½ë¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�����î¼ï¿½ï¿½ï¿½ê¾3+4+5=4+3+5

������������������棬����ò²ï¿½ï¿½ï¿½ï¿½ï¿½ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�������ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½

����355��423��423������

����258���� �� ��340������

����a��268��268+�� ��

����35+42+65=35+()+( )

�����ü½á£ºï¿½ï¿½ú¿ï¿½ï¿½ï£ï¿½í¬ñ§ï¿½ç¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¶ï¿½ï¿½ü°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ó»ô¾ï¿½ø´ï¿½ï¿½ï¿½ï¿½â£¬ñ§ï°ï¿½ï¿½ï¿½é²»ï¿½ï¸ï¿½ï¿½ç£ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ü½ï¿½ä¹ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ò²ï¿½ü·ï¿½ï¿½ö£ï¿½í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµä¹ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½õ»ï¿½ï¿½ø£ï¿½

苏教版加法交换律教学设计 加法交换律教学重点篇十一

�����������������ð¡ñ§ï¿½ï¿½ñ§ï°ï¿½ï¿½ñ§ï¿½ä±ï¿½ï¿½ï¿½æ¸ï¿½ï¿½ï¿½ò²ï¿½ï¿½ï¿½ï¿½ï¿½ç½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ì½ï¿½ï¿½ï¿½ä»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ó¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ðµï¿½ï¿½ï¿½ï¿½î¾­ï¿½é£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ú´ë»ï¿½ï¿½ï¿½ï¿½ï¿½êµï¿½ö¶ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ù´ï¿½ï¿½ì£¬ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ïµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§öªê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½õ¹ï¿½ï¿½ï¿½î³éµä¹ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ó¦ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

�����ì²ä·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì²ä´ï¿½ï¿½é¾³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¶¨ï¿½éµï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ê¹ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¸ï¿½ï¿½ï¿½ò»ï¿½ã£¬ï¿½é¾ï¿½ï¿½åµ½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½öªï¿½ï¿½ï¿½ì£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½é¸ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½

������ñ§ä¿ï¿½ê£ºì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ü¹ï¿½ï¿½ï¿½ï¿½ï¿½ä¸ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ã¶¨ï¿½é¹ï¿½ï¿½ì£ï¿½í¨ï¿½ï¿½ï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð±è½ïºí·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½î¶¯ï¿½ð»ï¿½ã³é¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������ñ§×¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã½ï¿½ï¿½î¼ï¿½ï¿½ï¿½

������ñ§ï¿½ï¿½ï¿½ì£ï¿½

����

����1.������â¡ï¿½ï¿½ï¿½ï¿½ï¿½äºï¿½ä¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ø´ï¿½ï¿½ï¿½é£º

����3��4��7������4��3��7������3��4��4��3

����2.���������龰����ê¾ï¿½ï¿½ï¿½ï¿½í¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½û²ì£¬í¼ï¿½ð¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ï¢ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½òªï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½

����3.���ô½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£º

����40��56��96��ç§ï¿½×£ï¿½56��40��96��ç§ï¿½×£ï¿½40��56��56��40

�����������룺�ç·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½í¶ï¿½ï¿½ï¿½ï¿½ä£¿

����

����1.���������ë²ï¿½ï¿½ë£¬ï¿½ï¿½ï¿½ç»ï¿½ï¿½ï¿½ï¿½ï¿½ö¤ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ï¿½ï¿½ö¤ï¿½ï¿½

����2.ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¤ï¿½ï¿½ï¿½ï¿½ê¦ñ²ï¿½ï¿½ö¸ï¿½ï¿½ï¿½ï¿½

����

����1.í¬ñ§ï¿½ï¿½ï¿½ï¿½ï¸ï¿½û²ï¿½ï¿½ð¾ù³ï¿½ï¿½äµï¿½ê½ï¿½ï¿½ëµò»ëµï¿½ã·¢ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ä»ï¿½ëµï¿½ï¿½ï¿½ã·¢ï¿½öµä¹ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½í²ï¿½ï¿½ä¡£ï¿½ï¿½ð¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½ï¿½ï¿½

����2.��ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï²ï¿½ï¿½ï¿½ä·ï¿½ê½ï¿½ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô±ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é±è½ï¿½ï¿½é·³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¾ï¿½è¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ø£ï¿½ï¿½ï¿½ò»ï¿½ô£ï¿½ï¿½ï¿½ï¿½ï¿½ï²ï¿½ï¿½ï¿½ä·ï¿½ï¿½å¡ï¿½ï¿½ï¿½ä¸ï¿½ï¿½í¼ï¿½î±ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����

����1.����ñ§ï¿½ï¿½ï¿½é¼ó·ï¿½ï¿½ï¿½èµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë·ï¿½ï¿½í³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¾ï¿½ï¿½î³é¹ï¿½ï¿½ú¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë·ï¿½ï¿½í³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ç·ï¿½ï¿½ð½ï¿½ï¿½ï¿½ï¿½éµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â²ï¿½ï¿½ë¡£

����2.ñ§ï¿½ï¿½ñ¡ï¿½ñ²¿·ö²ï¿½ï¿½ë£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¾ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ë£¬ï¿½ï¿½ê±ï¿½ï¿½ï¿½ï¿½ö¸ï¿½ï¿½ï¿½ï¿½

����3.��������ò»ï¿½ö²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½è·ï¿½ä£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¤ï¿½ã³ï¿½ï¿½ï¿½ï¿½ûµä£ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã³ï¿½ï¿½ï¿½ï¿½û¡ï¿½

����4.ì½ï¿½ö£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ë¼ï¿½ï¿½ï¿½ï¿½îªê²ã´ö»òªï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½æ·ï¿½ï¿½ï¿½ï¿½ë£¿

����

����1.��í¬ñ§ï¿½ï¿½ï¿½ï¿½ò»ï¿½ë£¬ï¿½ï¿½ç°ñ§ï¿½ï¿½ï¿½ï¿½öªê¶ï¿½ï¿½ï¿½ï¿½ð©ï¿½ø·ï¿½ï¿½ãµï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½

����2.�������ç¾ï¿½ï¿½ï¿½ï¿½ï¿½ò»ï¿½è£ï¿½ï¿½ï¿½ë­ñ§ï¿½ï¿½ï¿½ï¿½ã¡ï¿½

������1�����������������ïºï¿½ï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½

����300+600=����+��������+55=55+420 ����+65=����+35

������2����ï¸ï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����270+380=380+270 b+800=800+b

������3�����ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ð´ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ð´ð´ï¿½ï¿½ï¿½ô°é¡ï¿½

����25+49+75=����+����+����

����ñ§ï¿½ï¿½ð´ï¿½ï¿½ï¿½ï¿½ê½ï¿½ôºï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½û²ï¿½ï¿½ï¿½ð©ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½î»ï¿½ã£ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½ï¿½ê½ï¿½ð£ï¿½ï¿½ï¿½ï¿½ï¿½îªï¿½ï¿½ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½è½ï¼òµ¥£ï¿½ëµëµï¿½ï¿½ï¿½ï¿½ë·¨ï¿½ï¿½

����

����í¨ï¿½ï¿½ï¿½ï¿½ú¿îµï¿½ñ§ï°ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð©ï¿½õ»ï¿½ëµò»ëµï¿½ô¼ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ãµä·ï¿½ï¿½æ¡£

���������î±à¼­ï¿½ï¿½ï¿½ï¿½ï¼ï¿½ï¿½

苏教版加法交换律教学设计 加法交换律教学重点篇十二

����

����1��öªê¶ï¿½ë¼¼ï¿½ü£ï¿½ï¿½ù½ï¿½ï¾ï¿½ï¿½ï¿½ï¿½ï¿½é¾³ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éµäºï¿½ï¿½å¡£

����2�������뷽����������ä¸ê½ï¿½ó±ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ó¦ï¿½ã¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é½ï¿½ï¿½ï¿½ò»ð©ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¡£

����3�����ì¬ï¿½ï¿½ï¿½ï¿½ï¿½öµï¿½û£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ü³é¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã£ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ä£ï¿½ï¿½ï¿½õ¹ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ä»ï¿½ï¿½ï¿½ï¿½ï¿½ð¡ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½û²ì£¬ï¿½è½ï£ï¿½ï¿½ï¿½ï¿½ó£¬¸ï¿½ï¿½ï¿½ï¿½ä³ï¿½ï¿½ï¿½ë¼î¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

����

������ê¶ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½éµäºï¿½ï¿½å¡£

����

��������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ó£¬¸ï¿½ï¿½ï¿½ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

����

������ã½ï¿½ï¿½î¼ï¿½ï¿½ï¿½

����

����ò»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°

������ò»ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ñ§ï¿½ï¿½ï¿½

������ñ§ï¿½ï¿½ù£ï¿½p29ò³ï¿½ï¿½2�������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½×¢ï¿½ï¿½

����1��������2�龳í¼ï¿½ï¿½ï¿½ï¿½ï¢ï¿½ð³ï¿½ï¿½ï¿½ê½ï¿½ï¿½

����2������ï²ï¿½ï¿½ï¿½ä·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ï¿½

����3��í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ï¿½ï¿½ã·¨

����4����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¿½

����88+104+96 88+��104+96��

����=192+96 =88+200

����=288 =288

����5���ô±ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê½ï¿½ï¿½ï¿½ã·¢ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ï¿½ï¿½ô¼ï¿½ï¿½ä»ï¿½ëµò»ëµï¿½ï¿½

����������ñ§ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ù£ï¿½ï¿½ï¿½ñ§ï¿½ì²ï¿½p29ò³ï¿½ï¿½2���������ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½×¢ï¿½ï¿½

������ñ§ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ú²ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ç°ï¿½ï¿½ï¿½ï¿½ñ²ï¿½ï¿½ö¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ñ§ï¿½é£©

������������ñ§ï¿½ï¿½ï¿½

����1�����

����387+425=�� ��+ 387 525+�� ��=137+ 525

����300+600=�� ��+�� �� �� ��+65=�� ��+35

����2������

����56+68 150+��25+75��

����150+25+75 50+b

����b+50 68+56

����a+b+100 a+(b+100 )

������������ì½ï¿½ï¿½

������ò»ï¿½ï¿½ð¡ï¿½é»¥ì½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬í¬ï¿½ï¿½ï¿½ï¿½ñ§ï°ð¡ï¿½ï¿½ï¿½ú»ï¿½ï¿½à½»ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð¡ï¿½ï¿½ò²ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ëµï¿½ï¿½ï¿½ï¿½ï¿½çºã£ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê±ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï°ð¡ï¿½ï¿½ï¿½ï¿½ê¦ï¿½ï¿½ï¿½â¡£ï¿½ï¿½

����������ñ§ï¿½ï¿½ï¿½ï¿½è·ï¿½ø¼ï¿½ï¿½ã£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ö¹ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ì½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ê¦ñ²ï¿½ø¸ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ö¡ï¿½ï¿½õ¼ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½úµï¿½ï¿½ï¿½ï¿½â£©

����������ê¦ï¿½ï¿½ï¿½ï¿½ì½

����1������ð¡ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

������1����ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â£¬ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½

������2����ê¦ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ñ§ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

������3���������ä¸ï¿½ï¿½ê¾ï¿½ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½éºí½ï¿½ï¿½ï¿½é£ï¿½

������4������ä¸ï¿½ï¿½ê¾ï¿½ï¿½ð©ï¿½ï¿½ï¿½ã¶¨ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½åµã£¿

����2����ê¦ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ôµï¿½ï¿½ë²»í¬ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½í¬ñ§ï¿½ã±¨ï¿½ô¼ï¿½ï¿½ä½ï¿½ï¿½ï¿½ë¼â·ï¿½ë·½ï¿½ï¿½ï¿½ï¿½

�����ä¡ï¿½ï¿½ï¿½ï¿½ñµï¿½ï¿½ï¿½ï¿½1--3�������4��ñ¡ï¿½ï¿½ï¿½ï¿½5��ë¼ï¿½ï¿½ï¿½â£©

����1�����ý¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½â¡£

������1��78+25+22 =78 +�� ��+25

������2��376+175+25=376 +�� + ��

����2�����ߡ�

����147+��72+28�� a+(b+100 ��

����a+b+100 147+72+28

����3��������������⡣

����52+27+73 285+15+77+23

��������ð¡ï¿½á£ºì¸ì¸ï¿½ï¿½ï¿½ï¿½ê²ã´ï¿½õ»ï¿½ï¿½ï¿½ê²ã´ï¿½ï¿½ï¿½ü£ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ð£¿£ï¿½ñ§ï¿½ï¿½ï¿½ü½á²»ï¿½ï¿½ï¿½ï¿½ï¿½äµø·ï¿½ï¿½ï¿½ï¿½ï¿½ê¦òªï¿½êµï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ü½á£©

�����塢������

������ò»ï¿½ï¿½ï¿½ï¿½ê¾ï¿½ï¿½ï¿½ï¿½ï¿½

����1����駼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ã¶¨ï¿½ï¿½ï¿½ï¿½ï¿½

������1��450+320=�� ��+ 450 65+95=95+�� ��

������2���� ��+ 100 =100+150 250+�� ��=125+250

������3��78+25+22 =��78 + ��+�� ��

������4��495+125+75=495 +�� + ��

����2���������ð©ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½é£ï¿½ï¿½ï¿½ð©ï¿½ï¿½ê½ï¿½ï¿½ï¿½ï¼ó·ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½é¡ï¿½

������1��a + �� 30+9 ��=a+ 30+9

������2��15+ ( 7+b )= (15 + 7 )+b

������3��10 + 20 + 30 + 40 =10 + (20 + 30) + 40

����3�����ߡ�

����87+22+78 ��79+83)+17

����498+125+75 498+(125+75)

����(138+136��+162 87+��22+78 ��

����79+��83+17�� 138+136+162

����4�������㡣

����98+72+28 215+85+73+27

�������������巴����

������òµï¿½ï¿½ï¿½ï¿½

声明:准根文档网所有作品(图片、文字)均由用户自行上传分享,仅供网友学习交流。若您的权利被侵害,请联系 saizw@outlook.com