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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,*,3,的倍数的特征,小学数学五年级下册,因数与倍数,复习导入,请把下面各数填到相应的圈内。,2,的倍数,5,的倍数,43 26 78 15 60 32 25 90 51,新知探究,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,3,的倍数特征,你发现了什么？,3,的倍数,各个数位上的数字和,12,1,2,3,15,1,5,6,1,8,9,2,1,3,2,4,6,18,21,24,新知探究,3,的倍数的特征,一个数,各个数位上数字之和,是,3,的倍数，这个数就一定是,3,的倍数。,新知探究,在下面的数中圈出,3,的倍数。,53 87 36 65 60 128 453,新知探究,判断。,（,1,）个位上是,3,、,6,、,9,的一定是,3,的倍数。（）,（,2,）是,3,的倍数的数一定是,6,的倍数。（）,（,3,）,3,的倍数一定是奇数。（）,（,4,）同时是,2,、,3,的倍数的数一定是,6,的倍数。（）,新知探究,在中填几，这个数就是,3,的倍数。,760,5,（,0,、,3,、,6,、,9,）,17,（,1,、,4,、,7,）,找出最小的数然后依次加,3,巩固练习,巩固练习,下面用数字卡片摆出的数中哪些是,3,的倍数？在每,个数后面加一张卡片，使这个三位数成为,3,的倍数。,2,4,8,5,7,4,6,9,新知探究,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,同时是,2,，,3,和,5,的倍数特征,你发现了什么？,1.,判断一个数是否同时是,2,和,3,的倍数的方法：看这个数是否同时具备,2,和,3,的倍数的特征。,2.,判断一个数是否同时是,3,和,5,的倍数的方法：看这个数是否同时具备,3,和,5,的倍数的特征。,3.,判断一个数是否同时是,2,，,3,和,5,的倍数的方法：看这个数是否同时具备,2,，,3,和,5,的倍数的特征。,新知探究,新知探究,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,9,的倍数特征,你发现了什么？,9,的倍数,各个数位上的数字和,18,1,8,9,27,2,7,9,3,6,9,4,5,9,5,4,9,36,45,54,新知探究,9,的倍数的特征,一个数,各个数位上数字之和,是,9,的倍数，这个数就一定是,9,的倍数。,新知探究,课堂小结,通过本节课学习你收获了什么？,
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