首页 苏教版六年级下册《解决问题的策略(鸡兔同笼)》教案(2)

苏教版六年级下册《解决问题的策略(鸡兔同笼)》教案(2)

举报
开通vip

苏教版六年级下册《解决问题的策略(鸡兔同笼)》教案(2)解决问题的策略---假设一、复习导入师:同学们,回顾一下,我们已经学习了哪些解决问题的策略?生:画图、列表、一一列举、倒推、假设。(增)师:假设是我们上学期刚学过的一种策略,当已知总量同时分配给两个未知量,并告诉我们这两个未知量之间的关系时。我们可以利用倍数关系或相差关系把两种未知量假设成一种未知量来解题,可以使数量关系更清晰,计算更简便。                                                                                         ...

苏教版六年级下册《解决问题的策略(鸡兔同笼)》教案(2)
解决问题的策略---假设一、复习导入师:同学们,回顾一下,我们已经学习了哪些解决问题的策略?生:画图、列表、一一列举、倒推、假设。(增)师:假设是我们上学期刚学过的一种策略,当已知总量同时分配给两个未知量,并告诉我们这两个未知量之间的关系时。我们可以利用倍数关系或相差关系把两种未知量假设成一种未知量来解题,可以使数量关系更清晰,计算更简便。                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  师:是的,利用这些策略可以帮助我们更方便的解决一些实际问题。这节课我们就来继续学习解决问题的策略。(板书:解决问题的策略)二、教学新知,感知策略1、同学们,我们一起先来研究一道千古名题,在数学界把它叫做“鸡兔同笼”问题。早在1500多年前,在《孙子算经》中就记载着“鸡兔同笼”的问题,我们一起来看题。媒体出示:鸡兔同笼,一共有8只,数一数腿有22条,你知道鸡和兔各有多少只吗?(读一读)师:看懂了吗?题中给出了什么条件?生:已知鸡兔共8只,共有22条腿。师:对,要同时满足这两个条件,那么腿为什么会比头多呢?生:因为每只鸡有两条腿,每只兔有4条腿。师:哦,这个问题好像有点幼稚,却是题目背后所隐藏的重要条件。原来22条腿是由两种不同动物的腿组成,好像很难直接算出鸡兔的数量(份数),你准备怎样解决这个问题?生:用假设的策略师:下面我们就来继续研究用假设的策略解决问题的方法。2、鸡和兔一共有8只,你可以怎样假设?生:假设8只全是鸡,或假设8只全是兔师:同学们的想法真棒,你们都是把两个未知量假设成了一个未知量。课前,老师请了一个二 年级 六年级体育公开课教案九年级家长会课件PPT下载六年级家长会PPT课件一年级上册汉语拼音练习题六年级上册道德与法治课件 的小朋友做这道题,提示他通过假设,她居然做出来了,你知道他是借助什么方法做的吗?生:画图师:你猜对了,她借助画图的策略把这道题做出来了,我们也来试试吧,完成作业纸上第1题。媒体出示:按步骤画图解决问题用一个圆表示一个小动物,用“/”表示小动物的腿假设8只都是鸡,给每只鸡各画上2条腿,通过比较发现画的腿的总数比实际22条腿少6条,我们把这种差距叫做总量差。为什么会少6条呢?因为实际不全是鸡,一只兔比一只鸡多2条腿,我们把这种差距叫做个量差,那么要再给其中的几只动物添上2条腿,使画出的腿正好是22条。6里面有3个2条,要把3只鸡调整为兔。想:假设8只都是( ),总量差是( ),个量差是( )。总量差里面有( )个个量差,所以把( )只( )调整为( )。假设8只都是兔,给每只兔各画上4条腿,发现画的腿的总数比实际22条腿多10条,总量差是10。根据矛盾就要进行调整,因为一只兔比一只鸡多2条腿,个量差是2,那么要给其中的几只动物去掉2条腿,使画出的腿正好是22条。10条里面有5个2条,要把5只兔调整为鸡。想:假设8只都是( ),总量差是( ),个量差是( )。总量差里面有( )个个量差,把( )只( )调整为( )师:现在请把你的数学思考用计算的方式表示出来。我们得到的 答案 八年级地理上册填图题岩土工程勘察试题省略号的作用及举例应急救援安全知识车间5s试题及答案 是否正确呢?可以进行检验,看是否等于22只。小结:同学们,我们来回顾一下刚才我们是如何解这道题的,先提出假设,再进行比较,发现有总量差,再根据调整,用总量差÷个量差=两一个量的数量三、巩固练习4、其实,日本也研究过“鸡兔同笼”问题,只不过他们把名称改了,他们把这类题叫做“鹤龟算”。名称虽然改了,但与“鸡兔同笼”问题是一样的,龟就相当于兔,鹤就相当于鸡,你打算怎样解决?(用假设的策略)你们想借助画图来解决吗?为什么?(太多)你能列式解答吗?完成作业纸第2题,选择一种假设的方法列式解答并检验。5、下面我们再来看一道题师:题目读懂了吗?你想说什么?生:单打每桌2人,相当于鸡;双打每桌4人,相当于兔。师:你真厉害,又把这题归结为“鸡兔同笼”问题,可以用什么策略解决。(假设)完成后交流并检验。小结:看来“鸡兔同笼”问题,不仅限于鸡和兔的问题,它是一类数学问题的模式。比如“龟鹤”“单打双打”……师:可以是牛羊吗?(不可以)为什么?生:牛和羊都是四条腿师:那这两样事物应该有什么特点?(两样事物的每份数不一样)6、嗯、又如生活中我们存硬币的问题:出示例题,读题,你觉得要注意什么?(单位换算)5角=0.5元请列式解答7、今天我们运用假设的策略解题时,都是把两个事物假设成同一个事物,其实并不是只能这样假设。正如这道题:全班42人去公园划船,租10只船正好坐满。每只大船坐5人,每只小船坐3人。租的大船、小船各有多少只?共租10只船,我们可以假设小船和大船各一半。借助列表的策略来分析解决问题,请同学们完成作业纸9、这两种方法有什么共同点?先假设,再比较,然后进行调整!假设----比较-----调整-----检验7、比一比(1)全班42人去公园划船,租了6条大船,4条小船,每只大船比小船多坐2人。每只大船和小船各坐多少个人?(2)全班42人去公园划船,租10只船正好坐满。每只大船坐5人,每只小船坐3人。租的大船、小船各有多少只?已知求策略数量关系式总数  份数每份数假设总数÷份数=每份数总数 每份数份数假设总量差÷个量差=两一个量的数量10、 总结 初级经济法重点总结下载党员个人总结TXt高中句型全总结.doc高中句型全总结.doc理论力学知识点总结pdf :同学们,今天我们学习了用什么策略来解决问题?用假设的策略解决问题有哪些过程?先进行假设,在进行比较,发现矛盾后的总量差,再根据个量差进行调整,用总量差÷个量差=两一个量的数量。 板书:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
本文档为【苏教版六年级下册《解决问题的策略(鸡兔同笼)》教案(2)】,请使用软件OFFICE或WPS软件打开。作品中的文字与图均可以修改和编辑, 图片更改请在作品中右键图片并更换,文字修改请直接点击文字进行修改,也可以新增和删除文档中的内容。
该文档来自用户分享,如有侵权行为请发邮件ishare@vip.sina.com联系网站客服,我们会及时删除。
[版权声明] 本站所有资料为用户分享产生,若发现您的权利被侵害,请联系客服邮件isharekefu@iask.cn,我们尽快处理。
本作品所展示的图片、画像、字体、音乐的版权可能需版权方额外授权,请谨慎使用。
网站提供的党政主题相关内容(国旗、国徽、党徽..)目的在于配合国家政策宣传,仅限个人学习分享使用,禁止用于任何广告和商用目的。
下载需要: 免费 已有0 人下载
最新资料
资料动态
专题动态
is_477730
暂无简介~
格式:doc
大小:50KB
软件:Word
页数:15
分类:
上传时间:2022-08-09
浏览量:2