小数点的移动和单位换算公开课获奖课件.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,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,小数移动与单位换算,第1页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,例1:把0.07分别扩大到本来10倍、100倍、1000倍，各是多少？,0.0710,0.7,7,70,【一题导解】,0.07100,0.071000,第2页,3.210,3.2100,3.21000,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,例,2,：,把,3.2,分别缩小到原来 ，各是多少？,0.32,0.032,0.0032,【一题导解】,第3页,1,米,=100,厘,米,100+45=145,厘米,95,状元成才路,状元成才路,3,、填一填,0.95,米（）厘米,0.95,100=95,厘米,3公斤=()吨,3,1000=,0.003,吨,1,米,45,厘米（）厘米,进率,低级单位 高级单位,进率,0.003,145,【一题导解】,第4页,_,1,10,_,1,100,_,1,1000,【一题,导学】,（扩大到,倍）,（缩小到,几份之一）,小数点，本领大，走一走，数变化。右走扩大用乘法，左走缩小用除法。移动缺位也不怕，快用“0”来补足它。,口诀,：,第5页,一想：（单位间进率是多少）,二看：（大化小还是小化大）,三算：（大化小乘以进率，小数点右移；小化大除以进率，小数点左移）,单位换算措施：,【一题,导学】,第6页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,0,2 9 6,例1：在括号里填上合适数。,2.96,10,(),100,(),1000,(296 ),2 9 6,.,29.6,2 9 6,.,0,0.296,小数点向,右,移动,位,小数点向,左,移动,位,小数点向,右,移动,位,一,两,三,.,【一题,导学】,第7页,例,2,：,我最棒，直接填得数。,2.87,10=3.9,1000=,34.81,10=2,1000=,0.67,100,10=,12.5,100,1000=,0.002,3900,3.481,28.7,0.067,1.25,【一题,导学】,第8页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,例3：乐乐饰品店购进10个海宝玩具共花了45.5元，假如再购进1000个这样玩具，需要多少钱？,答：需要,45500,元。,45.5 X,（,100010,）,=45500,（元）,45.5 10 X 1000=45500,（元）,【一题,导练】,第9页,300,86,进率,低级单位 高级单位,进率,例4：做一做，并说说改写措施。,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,6.32,8.035,0.43,5.6,0.3kg()g 0.86m2()dm2,6320米=()千米 8035公斤=()吨,4角3分=()元 5米6分米=()米,【一题,导练】,第10页,例5：判断。(对旳打“”，错打“”),(2)把公斤数改写成吨数，要除以1000。(),(3)由于580克=0.58公斤，因此6公斤580克就等于60.58公斤。(),(1),教室面积是,56.8,平方分米。,(),【一题,导练】,第11页,例：小明买东西付了50元钱，营业员将商品价格小数,点看错了一位，找给顾客45.75元，顾客说钱找多了，这,件商品对旳标价是多少？,50-45.75=4.25,（元,）,4.25,10=42.5,（元,）,答：这件商品对旳标价是42.5元。,【一题,导练】,第12页,例：把一种数小数点先向左移动两位，再向右,移动三位，成果得0.6，那么原数是多少？,0.6,100,1000=0.06,答：原数是,6,。,【一题,导练】,第13页,例：甲数是乙数,100,倍，若把乙数小数点向左移动,一位后是,56.01,，则甲数是多少？,56.01,10,100=56010,答：甲数是,56010,。,【一题,导变】,第14页,例：一种数小数点向左移动一位后比原数减少了46.8，原数,是多少？,46.8,（,10-1,）,=46.8,9,=5.2,5.2,10=52,答：原数是,52,。,【一题,导变】,第15页,谢谢大家聆听,第16页,