相逢一笑百媚生
幼苗
共回答了25个问题采纳率:76% 举报
总数有 8*7*6*5*4/(5*4*3*2*1)=56 .
因此选对的概率为 1/56 .
假如8个号码分别为12345678,每次选5个,则所有的组合为
12345,12346,12347,12348,12356,12357,12358,12367,
12368,12378,12456,12457,12458,12467,12468,12478,
12567,12568,12578,12678,13456,13457,13458,13467,
13468,13478,13567,13568,13578,13678,14567,14568,
14578,14678,15678,23456,23457,23458,23467,23468,
23478,23567,23568,23578,23678,24567,24568,24578,
24678,25678,34567,34568,34578,34678,35678,45678.
1年前
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