苏教版小数的意义和性质复习市名师优质课比赛一等奖市公开课获奖课件.pptx

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,*,小数意义和性质复习课,第1页,（一）小数计数单位和进率,知识点：,1,、,小数,计数单位,是,十分之一,、,百分之一,、,千分之一,分别写作,0.1,、,0.01,、,0.001,2,、,每,相邻,两个计数单位间,进率,是,10,。,练习题：,（,1,）说出下面各小数意义,0.3,0.03,0.003,意义,:0.3,里面有,3,个,0.1,0.06,0.21,2.1,20.705,第2页,（一）小数计数单位和进率,知识点：,1,、,小数,计数单位,是,十分之一,、,百分之一,、,千分之一,分别写作,0.1,、,0.01,、,0.001,2,、,每,相邻,两个计数单位间,进率,是,10,。,练习题：,（,2,）说出下面各小数计数单位,0.3,0.03,0.003,计数单位是,0.1,0.06,0.21,0.01,0.001,0.01,0.01,第3页,（二）小数性质和移动,知识点：,1,、,小数,末尾,添上”,0”,或去掉”,0”,小数,大小不变,练习题,不改变数大小,下面数中哪些,”,0,”,能够去掉,哪些,”,0,”,不能去掉,?,为何,?,3.90,米,0.30,元,500,米,1.80,元,0.70,米,0.04,元,600,千克,20.20,米,能够去掉,”,0,”,是,末尾,0,第4页,（二）小数性质和移动,知识点：,1,、,小数,末尾,添上”,0”,或去掉”,0”,小数,大小不变,练习题,假如在下面各数末尾添,”,0,”,哪些数大小不变,哪些数大小有改变,?,3.4,18,0.06,700,908,104.03,150,10.01,3.0,42.00,在小数部分末尾添,”,0,”,第5页,（二）小数性质和移动,知识点：,2,、,小数点,向右,移动,1,位,小数就,扩大,到原数,10,倍,移动,2,位,小数就,扩大,到原数,100,倍,移动,3,位,小数就,扩大,到原数,1000,倍,小数点,向左,移动,1,位,小数就,缩小,原数,10,倍,移动,2,位,小数就,缩小,原数,100,倍,移动,3,位,小数就,缩小,原数,1000,倍,练习题：,0.25,(),到原数,(),倍,2.5,扩大,10,(),缩小,了,10,倍,0.001,扩大,到原数,100,倍,0.1,缩小,了,100,倍,第6页,（二）小数性质和移动,知识点：,2,、,小数点,向右,移动,1,位,小数就,扩大,到原数,10,倍,移动,2,位,小数就,扩大,到原数,100,倍,移动,3,位,小数就,扩大,到原数,1000,倍,小数点,向左,移动,1,位,小数就,缩小,原数,10,倍,移动,2,位,小数就,缩小,原数,100,倍,移动,3,位,小数就,缩小,原数,1000,倍,练习题：,30.5,扩大,到原数,10,倍,3.05,缩小,了,10,倍,15.3,扩大,到原数,100,倍,0.153,缩小,了,100,倍,第7页,练习题：,1,、填上适当数,(1),把,3.6,小数点向,左,移动一位是,(),(2),把,3.14,小数点向,左,移动两位是,(),(3),把,0.03,扩大到它,(),倍是,30,(4),把,42,缩小,(),倍是,0.042,0.36,0.0314,1000,1000,2,、把,6.25,改写成下面数,它大小各有什么改变,?,62.5 0.625 625 0.0625,把,6.25,小数点,向,右,移动了,一,位,扩大,了原数,10,倍,得到,62.5,第8页,