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,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,二级,三级,四级,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,二级,三级,四级,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,二级,三级,四级,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,二级,三级,四级,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,二级,三级,四级,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,二级,三级,四级,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,二级,三级,四级,五级,*,第,2,单元 因数与倍数,课题,3,2,、,5,的倍数特征,第2单元 因数与倍数课题3 2、5的倍数特征,哪些号码是双号?,2,,,4,,,6,,,8,,,10,,,12,,,14,它们都是,2,的倍数。,一、情景导入,哪些号码是双号?2,4,6,8,10,12,14它们都是,在表中将2的倍数找出来仔细观察,你发现了什么?,二、自主探究,在表中将2的倍数找出来仔细观察,你发现了什么?二、自主探究,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,2,的倍数,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,123456789101112131415161718192,在表中将5的倍数找出来仔细观察,你发现了什么?,在表中将5的倍数找出来仔细观察,你发现了什么?,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,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,123456789101112131415161718192,2,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),三、知识梳理,2的倍数的特征 个位上是0、2、4、6、8的数,都是2,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,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,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,。,自然数中,是2的倍数的数叫做偶数(0也是偶数),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),5的倍数的特征,1.,下面哪些数是,2,的倍数?哪些数是,5,的倍数?哪些数既是,2,的倍数,也是,5,的倍数?,35 67 90 99 15 106,60 75 130 521 280 6018 8100,个位上是,0,的数既是,2,的,倍数也是,5,的倍数。,2,的倍数,5,的倍数,24,,,106,,,6018,35,,,15,,,75,90,,,60,,,130,,,280,,,8100,既是,2,的倍数也是,5,的倍数,做完这道题,,你发现了什么?,做一做,四、巩固练习,1.下面哪些数是2的倍数?哪些数是5的倍数?哪些数既是,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的倍数24,106,5的倍数35,90,15,60,75,,2.,下列数中,哪些是奇数?哪些是偶数?,33,98,8089,988,3678,0,565,123,355,1000,677,881,奇数,:,偶数,:,2.下列数中,哪些是奇数?哪些是偶数?33988089988,3.,按要求填空,(1)两个数位上的数一样,并且,是5的倍数。,(2)3 5 既是2的倍数,又是5的倍数。,(3)既是2的倍数,又是5的倍数,的最小三位数,3.按要求填空(1)两个,
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