六年级数学上册《百分数和分数、小数的互化》

麻城小学：郑冰Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.0.451.20.367复习一先把下面的小数化成分数，再说一说小数化分数的方法。先化成分母是10、100、1000的分数，再约分。小数分数Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.复习二先把下面的分数化成小数，再说一说分数化小数的方法。32563100781用分子除以分母分数小数Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.50%120%60%、40%你还想了解百分数的哪些知识？Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.1把0.24、1.4、0.123化成百分数。0.241.40.123百分数是分母为100的特殊分数。＝1231000241004101＝＝＝＝＝24%140%1410140100＝＝12.3100＝12.3%小数分母是100的分数百分数Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.做一做把下面各数化成百分数。0.5151%207%2.070.02542.5%400%想一想：怎样能很快地把小数化成百分数？Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.5151.%0＝把小数化成百分数，只要把小数点向右移动两位，同时在后面添上百分号。.Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.2把27%、135%、0.4%化成小数。27%135%0.4%＝27100＝＝0.271.351351000.41000.004百分数小数＝＝＝Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.把下面各百分数化成小数。21%0.210.990%4.5%0.045想一想：怎样能很快地把百分数化成小数？Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.21%0＝把百分数化成小数，只要把百分号去掉，同时把小数点向左移动两位。.21.0Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.我的收获今天我学习了百分数和小数的互化，我能算：1、小数化成百分数。0.7＝()%5＝（）%1.08＝()%0.305＝()%7050010830.5Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.2、百分数化成小数或整数。150%＝（）500%＝（）0.4%＝（）1.75%＝（）1.550.0040.0175Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.3＝0.75≈0.167＝1.6＝75%16.7%＝＝160%小数分数百分数把、、化成百数。34163513416351Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.把分数化成百分数，通常先把分数化成小数（除不尽时，通常保留三位小数），再把小数化成百分数。＝0.75≈0.167＝1.6＝75%16.7%＝＝160%3416351Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.4把17%、40%、12.5%化成分数。17%40%12.5%＝17100＝＝4010012.5100＝百分数分母是100的分数＝＝25125100018最简分数Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.把百分数化成分数，先把百分数改写成分数，能约分的要约成最简分数。17%40%12.5%＝17100＝＝4010012.5100＝＝＝25125100018Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.2、百分数化成分数。62.5%＝（）0.25%＝（）8%＝（）72%＝（）37.514014.32今天我学习了百分数和分数的互化，我能算：1、分数化成百分数。＝()%＝()%≈()%＝()%382511715085412522518Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.努力吧！Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.下面的正方形表示“1”，把各图中阴影部分按要求表示出来。用小数表示（）用分数表示（）用百分数表示（）10099%0.09用小数表示（）用分数表示（）用百分数表示（）201155%0.55Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.按由小到大的顺序排列下列各数。0.5410.0540.5043.9%2750Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.A：一位小数B：两位小数C：三位小数A把化成百分数时，百分号前一般保留（）。13Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.A：向左B：向右C：一位A把6.4%化成小数，先把百分号去掉，然后把6.4的小数点（）移动（）。DD：两位Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.B在一个自然数（0除外）后面添上一个“%”，这个自然数就（）。选一选A：扩大100倍B：缩小100倍C：减少100倍Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.小数0.61.25百分数55%分数382360%350.5511200.37537.5%125%1410.66766.7%Evaluationonly.CreatedwithAspose.Slidesfor.NET3.5ClientProfile5.2.0.0.Copyright2004-2011AsposePtyLtd.