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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,除数是两位数的除法,口算除法,一、复习导入,揭示课题,给小动物们找家。,4005,3609,18006,2804,24004,8004,300,200,70,80,600,40,8020,因为,80,里有几个,20,,,就可以分给几个班,,所以用除法计算。,怎样列式?,为什么用除法计算?,二、探究新知,80,20,有,80,面彩旗,每班分,20,面,可以分给几个班?,题目中已知一共有,80,面,彩旗,每班分,20,面,要,求,“,可以分给几个班,”,。,同学们,题目中已知的是,什么?要求的是什么?,4,(个),80,20,8020,等于几?,你是怎么想的?,想一想:,83,20,80,19,二、探究新知,80,20,4,4,有,80,面彩旗,每班分,20,面,可以分给几个班?,82,4,,,8020,4,。,( )个,20,是,80,,,8020,( )。,4,4,15,5,(,),,150,50,(,)。,( )个,50,是,150,,,15050,( )。,二、探究新知,120,30,4,4,3,3,3,3,3,15050,想一想:,122,30,120,28,你知道,15050,等于几吗?你是怎么想的?,三、知识运用,60,20,90,30,40,20,100,20,62,20,93,30,42,20,103,20,60,3,3,90,3,3,40,2,2,100,5,5,1.,口算下面各题,并说一说你是怎么想的。,6020,我是这么想的:,62,3,,,所以,6020,3,。,6220,我是这么想的:把,62,看成,60,,,6020,3,,所以,6220,3,。,三、知识运用,180,30,240,40,420,60,210,30,184,30,240,37,420,62,210,29,180,6,6,40,6,6,60,7,7,30,7,7,2.,口算下面各题,并说一说你是怎么想的。,24037,我是这么想的:把,37,看成,40,,,24040,6,,所以,24037,6,。,三、知识运用,30,2,40,3,80,3,90,5,60,30,120,40,240,80,450,90,2,60,3,120,3,240,5,450,口算下面各题,看看谁能全对。,302,我是这么想的:,32,6,,,所以,302,60,。,6030,我是这么想的:,302,60,,,所以,6030,2,。,3.,三、知识运用,30,180,270,30,80,200,280,40,1,6,9,2,5,7,4.,口算下面各题,看看谁能全对。,24030,因为,240,里有几个,30,,,就要捆几包,所以用,除法计算。,三、知识运用,240,30,8,(包),答:要捆,8,包。,为什么用除法计算?,怎样列式?,自己试着做一做。,同学们,题目中已知,的是什么?要求的是,什么?,题目中已知要寄,240,本,书,每包,30,本,要求,“,要捆多少包,”,。,5.,四、布置作业,作业:,第,72,页练习十二,第,4,题、第,5,题、,第,7,题。,
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