北师大版小学四年级下册数学第三单元小数乘法《买文具》课件培训资料.ppt

,子页,子页,子页,子页,子页题目,内容：,子页,子页,子页,子页,子页题目,内容：,子页,子页,子页,子页,子页题目,内容：,子页,子页,子页,子页,子页题目,内容：,内容：,子页题目,子页,子页,子页,子页,主页,子页,子页题目,子页,子页,子页,主页,子页,T,H,A,N,K,Y,O,U,*,北师大版 四年级下册 第三单元 小数乘法,问题,探究,练习,拓展,绿色圃中小学教育网www.L,绿色圃中小学教育网www.L,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2、一支圆珠笔,2,元，买,4,支要多少钱？,2,4=,2+2+2+2=,1、口 算：,25,4=,12,5=,7,20=,2.5,+,2=,300,2=,2角,4=,3.6-2.4=,4.7+2.6=,5,1.8=,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,你获得了什么信息？,你能提出什么数学问题？,文 具 店,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,答：买4块橡皮需要0.8元。,买4块橡皮需要多少钱？,绿色圃中小学教育网www.L,绿色圃中小学教育网www.L,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,笑笑是这样做的，你能看懂吗？,0.24 （）,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,买3把尺子需要多少元？,0.43 （）,1,2,3,0.4元4角,3412（角）,12角1.2元,0.431.2（元）,0.4,0.4,0.4,答：买3把尺子需要1.2元。,1.2 元,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,小数乘整数的意义,与,整数乘法的意义相同，,都是,求几个相同加数的和的简便运算。,2+2+2+2=2x4,0.2+0.2+0.2+0.2=0.2x4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,算一算：,0.7,1=,0.1,5=,0.4,6=,0.3,5=,0.02,4=,0.08,7=,0.7,0.5,2.4,1.5,0.08,0.56,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,比一比，谁最快,0.8,3=,7,0.5=,1.4,2=,0.7,10=,0.06,5=,4,0.09=,0.01,15=,2.1,4=,2.4,3.5,2.8,7,0.3,0.36,0.15,8.4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,40.3 =0.3 4,乘法交换律,你能计算,4,0.3,吗？与同学交流你的想法。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1、每千克苹果,3.2,元，妈妈买了,3千克,，一共要用多少元？,解决问题：,2、小明每小时走,5,千米，,1.5小时,可以走多少千米？,单价x数量=总价,3.2,3 =9.6,(元),速度x时间=路程,5,1.5=7.5,(千米),Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,解决问题：,1.一支钢笔3.5元，买8支要多少元？,2.一根跳绳要2.6米，做12根要用多长？,3.5x8=28（元）,2.6x12=31.2（米）,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,1.买4把卷笔刀需要多少元？涂一涂，算一算，,与同伴交流你的想法。,绿色圃中小学教育网www.L,绿色圃中小学教育网www.L,2.8元,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2.买6支铅笔需要多少元？与同伴交流你的想法。,60.3=,1.8元,答：,买6支铅笔需要1.8元,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,3.,0.3,3 0.2,8 4,0.2,3,0.5 0.4,4 0.1,9,0.7,2 6,0.2 0.6,4,0.9,1.5,1.4,1.6,1.6,1.2,0.8,0.9,2.4,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,4.涂一涂，填一填。,0.1,1,0.5,绿色圃中小学教育网www.L,绿色圃中小学教育网www.L,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,5.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,