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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,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,2,、,5,的倍数的特征,马郎小学 陈伟,1,、在,2,、,3,、,5,、,8,、,10,、,12,、,25,、,40,这几个数中，,40,的因数有几个？,5,的倍数有几个？,复习：,2,、在,6,、,10,、,12,、,15,、,18,、,20,这几个数中，哪些数是,2,的倍数？哪些数是,5,的倍数？,40,的因数有,2,，,5,，,8,，,10,，,40,。,5,的倍数有,5,，,10,，,25,，,40,。,2,的倍数有,6,，,10,，,12,，,18,，,20,。,5,的倍数有,10,，,15,，,20,。,3245 2963 8037 7231 12035 4570,你能快速判断下面这几个数，哪几个是,2,的倍数？哪几个是,5,的倍数？,哪些号码是双号？,2,，,4,，,6,，,8,，,10,，,12,，,14,它们都是,2,的倍数。,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,2,的倍数,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,2,的倍数的特征,个位上是,0,、,2,、,4,、,6,、,8,的数，都是,2,的倍数。（也就是能被,2,整除的数）,自然数中，是,2,的倍数的数叫做偶数（,0,也是偶数），不是,2,的倍数的数叫做奇数。,自然数,奇数,偶数,不能被,2,整除的数，个位上是,1,，,3,，,5,，,7,，,9,。,能被,2,整除的数，个位上是,0,，,2,，,4,，,6,，,8,。,最小的偶数是几？有没有最大的偶数？,最小的奇数是几？有没有最大的奇数？,最小的偶数是,0,，没有最大的偶数。,最小的奇数是,1,，没有最大的奇数。,考 考 你,给,2,的倍数涂上绿色。,19,104,36,65,48,153,287,78,104,36,48,78,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,5,的倍数,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,5,的倍数的特征,个位上是,0,或,5,的数，都是,5,的倍数。（也就是能被,5,整除的数）,2,的倍数,24,，,90,，,60,，,106,，,130,，,280,。,5,的倍数,35,，,90,，,15,，,60,，,75,，,130,，,280,。,2,的倍数,24,，,106,，,5,的倍数,35,，,90,，,15,，,60,，,75,，,130,，,280,。,60,，,280,。,90,，,130,，,既是,2,的倍数，又是,5,的倍数。,2,和,5,的共同倍数的特征,个位上是,”,0”,的自然数，既是,5,的倍数,又是,2,的倍数,.,思考：,奇数,+,偶数,=,（）；,奇数,+,奇数,=,（）；,偶数,+,偶数,=,（）。,奇 数,偶 数,偶 数,严谨认真,天天进步,
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