11234,12234,13345,14456,15567,17789,11345,11546,11567,11678,11789,12245,12256,12278,12289,13356,13367,13389,22345,22456,22567,22678,22789,33124,33456,33567,33678,33891,44156,44167,44567,44789,44678,44123,55678,55789,55123,55234,55612,55236,55238,55239,55894,55467,55194,66123,66124,66134,66789,66452,66158,66984,66258,66492,66384,77894,77456,77123,77852,77462,77951,77536,77956,77358,77149,88456,88123,88495,88159,88975,88123,88759,88457,88452,88469,88421,8859399456,99123,99785,99452,99126,99852,99741,99631,99586,99125,99764,99138,15589,16658,19984,16643,18824,15579,16627
答案:0-9可以组成 27216 组五位数的数据。
过程如下:
没有重复的数字的全部组合:A5/10,等于10x9x8x7x6,等于30240组;
0在首位、没有重复的全部数字组合:A4/9,等于9x8x7x6等于3024组;
所以,答案是:30240-3024等于27216。
第一个数有9种选择(不能选0)
第二个有9种
第三个有8种
第四个有7种
第五个有6种
一共:9*9*8*7*6=27216
9乘以8乘以7乘以6乘以5加上9乘以8乘以7乘以6乘以4
10*9*8*7*6 = 30240