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,*,2,的倍数的特征,座位号是多少的同学,应该从双号入口进,?,座位号为,2,，,4,，,6,，,8,，,10,，,2=1,2,4=2,2,6=3,2,8=4,2,10=5,2,这些数都是,2,的倍数。,个位上是：,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（,j,),数,。,0,，,2,，,4,，,6,，,8,你发现,2,的倍数有什么特征吗,?,的数都是,2,的倍数。,的倍数有：,2,，,4,，,6,，,8,，,10,，,12,，,14,，,16,，,18,下列数中，哪些是奇数，哪些是偶数,?,33,98,355,988,0,123,3678,8089,1000,655,5656,881,奇数,偶数,5,的倍数的特征,5,的倍数 又有什么特征呢？,在下表中找出,5,的倍数，并涂上颜色。看看有什么规律。,课本,18,页,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,个位上是,_,或,_,的数，是,5,的倍数。,0,5,2,的倍数,5,的倍数,既是,2,的倍数,又是,5,的倍数,24,90,60,106,130,280,35,90,15,60,75,130,280,90,60,130,280,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,?,24,35,67,90,99,15,60,75,106,521,130,280,P18,做完这道题，你有什么收获,?,个位上是,0,的数，既是,2,的倍数，又是,5,的倍数。,5 6,作业：,同步,P,7,再见,