1、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,*,苏教版 数学 五年级 上册,积,小数位数不够小数乘法,情景,导,入,探究新知,课堂小结,课后作业,小数乘法和除法,课堂练习,5,第1页,情景,导,入,6.70.3=,6.7,0.3,1,先按整数乘法算出积,67,3,1,一位小数,一位小数,两位小数,.,再看因数中一共有几位小数就从积右边起数出几位，点上小数点。,2 0 1,.,0,2,0,2,第2页,九折,探究新知,例,1,小,明在阳台上摆放了一个花架，它底边是边长,0.28,米正方形。这个花架占地面积是多少平方米？,0.28,0.28,（,平方米,）,要
2、从积右边起数出几位点上小数点？位数不够怎么办？,0.2 8,0.2,8,2 2 4,5 6,7 8 4,第3页,小明在阳台上摆放了一个花架，它底面是边长,0.28,米正方形。这个花架占地面积是多少平方米？,0.0784,答：花架占地面积是,平方米。,0.28,0.28,（,平方米,）,0.0784,在积里点小数点,时，位数不够，,在前面用,0,补足。,0.2 8,0.2,8,2 2 4,5 6,7 8 4,0,.,0,第4页,练一练,你能给下面各题积点上小数点吗？,0.7,0.9,6 3,1.0 5,0.0 6,6,3,0,0.1,8,0.3,5,4,.,.,.,0,0,0,0,0,第5页,课
3、堂练习,0.430.15,(,),0.0645,4,添,0,第6页,填一填。,8.5,小数点先向右移动两位，再向左移动三位，结果是（）。,0.85,第7页,你,能给下面积点上小数点吗？,0,0,0,.,.,.,0,0,第8页,依据,1283,384,，直接写得数。,12.80.3,1.280.3,0.1280.3,0.1280.03,3.84,0.384,0.0384,0.00384,第9页,口算,。,2.50.4,0.10.3,0.1220,1.250.8,3.20.2,1.50.4,105.6,0.20.3,1,0.03,2.4,1,0.64,0.6,56,0.06,第10页,不,计算，说
4、出下面各题,积,有几位小数。,2.35.4,0.250.37,8.10.04,0.092.004,2,位,4,位,3,位,5,位,第11页,计算下面各题，并用计算器验算。,0.270.15,0.0380.32,0.0491.42,0.140.32,0.183.2,0.030.84,0.0405,0.01216,0.06958,0.0448,0.576,0.0252,第12页,用竖式计算下面各题。,0.74,2.03 0.025,1.38,2,2.0,3,0.7 4,2,3,1.3 8,0.0 2 5,0,0,0,=1.5022,=0.0345,2,0,5,1,1,8,2,1,1,4,9,6,6
5、7,2,4,5,0,第13页,火眼金睛,辨对错。,更正：,0.018,第14页,更正：,633.6,第15页,更正：,0.042,第16页,一块长方形,铝板，长,0.84,米，宽,0.6,米；一块正方形铝板，边长,0.7,米。哪一块铝板面积大一些,?,大多少平方米,?,答：长方形铝板面积大,一些,大,0.014,平方米。,0.840.6,长方形铝板：,正方形铝板：,0.70.7,0.504,0.49=0.014,（平方米）,=0.504,（平方米）,=0.49,（平方米）,第17页,这节课你们都学会了哪些知识？,课堂小结,在积中点小数点，位数不够时，要在前面用,0,补位；积小数末尾有,0,，要先点上小数点，再依据小数性质进行化简。,第18页,1.,从教材课后习题中选取；,2.,从课时练中选取。,课后作业,第19页,
浙ICP备2021020529号-1 | 浙B2-20240490 
