北师大版四年级下册数学《练习三》教学内容.ppt

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,*,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,*,制作人：程红,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,认真思考,笑笑演讲时的平均语速为每分,215,个字，在“迎国庆演讲比赛”中，需要演讲,15,分，笑笑准备了,3000,字的 稿子，够吗？,+,（1）,估：,215 x 15,3000,（个）,200,（,2,）,215 x 15=3225,（个）,32253000,答：不够。,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.,学以致用,58 x18=4534,（）,88x34=318,（）,150 x40=600,（）,350 x70=2450,（）,不用计算，直接判断对错。,想一想，怎样判断。小组内说一说判断方法。,60,20,90,30,x,x,x,x,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,293+285+292+297+302+316+312,3007,=2100,（元）,每天的营业额大约是,300,元，,9,月份有,30,天,30030=9000,（元）,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,30 5 3,450,（根）,90 5,450,（根）,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.,1035369,672 672,159159,834834,276 276,951951,438438,1172421,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,11018,1980,（千米）,答：大约在长沙和韶关之间。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,2294-1980=314,（,千米）,110,3=330,（千米）,3+,18+3-12=12,（时）,答：中午,12:00,左右。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,118,12,=1200,（名）,答：能容纳,1200,名乘客。,100,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,190,5=950,（元）,1000,950,答：,1000,元够了。,Evaluation only.,Created with Aspose.Slides for.NET 3.5 Client Profile 5.2.0.0.,Copyright 2004-2011 Aspose Pty Ltd.,基本训练,72x124=,56x456=,603x34=,460 x18=,8928,25536,20502,8280,先用两位数个位上的数去乘三位数，得数的末位要和两位数中的个位数对齐,再用两位数十位上的数去乘三位数，得数的末位要和两位中的十位对齐,最后再把两次的积相加。,小组成员先计算，并相互检查。结合计算说一说计算方法。,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.,