分数和小数的互化.ppt

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,R五年级下册,第1课时分数和小数的互化（1）,6.分数和小数的互化,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,1.说出下列各分数的分数单位和有几个这样的单位。,引入新课,2.填空。(1)0.6表示()分之()。0.09表示()分之()。(2)0.5表示()分之()，写作。(3)0.006里面有()个千分之一，它表示()分之()，写成分数是。,十,六,百,九,十,五,10,5,6,千,六,1000,6,1,把一条3m长的绳子平均分成10段，每段长多少米？,310=0.3（m）,310=（m）,如何列式计算？,探究新知,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,0.3m和m有什么关系？,310=0.3（m）,310=（m）,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,把小数化成分数时,原来有几位小数,就在1的后面写几个0作分母,原来的小数去掉小数点作分子。,小数化成分数的方法：,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,问题：每段长多少米？,35=0.6（m）,35=（m）,把一条3m长的绳子平均分成5段。,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,35=0.6（m）,35=（m）,3,5,小数化成分数，需要注意什么？,需要化简的分数，要化简成最简分数。,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,100,100,123,1000,6,25,做一做,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,1.填空,把0.25化成分数时，因为0.25是（）小数，所以就在1后面写（）个0作（），把0.25去掉小数点作（），最后是（）。,两位,2,分母,分子,达标检测,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,2.分别用小数和分数表示下面每个图形的阴影部分。,小数:()小数:()分数:()分数:(),0.07,0.2,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,3.哪两只手套是一双，连一连。,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,0.65=（）,1.07=（）,0.5=（）,4.下面的小数化分数是否正确？,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,0.76.130.080.651.075,0.7=,7,10,6.13=,100,13,0.08=,8,100,2,25,=,25,2,0.65=,100,65,=,13,20,20,13,1.075=,1000,1075,215,200,5、把下面的小数化成分数。,6,43,40,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,小数表示