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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,太平镇邢村小学 燕汝庆,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,验证猜想,498 756,1335 5534,一个数各位上的数的和是,3,的倍数,这个数就是,3,的倍数。,我的发现,学习方法,猜想,验证,结论,智勇大闯关,第一关,下面哪些数是,3,的倍数?在下面()里面画“,”,42 78 111 165 655 5988,()()()()()(),95 311 82 2037 2222,()()()()(),42 78 111 165 655 5988,()()()()()(),95 311 82 2037 2222,()()()()(),智勇大闯关,第二关,在里填上一个数字,使这个数成为,3,的倍数。,24 ,里可以填(),127 ,里可以填(),306 ,里可以填(),0,、,3,、,6,、,9,2,、,5,、,8,0,、,3,、,6,、,9,探索真快乐!,看谁能很快的判断出,369124,这个数是不是,3,的倍数。,我的发现,在判断一个数是不是,3,的倍数时,我们只要将不是,3,的倍数的数位上的数加起来就可以了。计算过程中还可以运用“加法结合律”找,3,的倍数。,我是小法官,判断下面的数是不是,3,的倍数?,123456789123456,畅所欲言,上了这节课,我的收获很多,
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