题库搜索>问题求解PS-12738
A company has assigned a distinct 3-digit code number to each of its 330 employees. Each code number was formed from the digits
2, 3, 4, 5, 6, 7, 8, 9
and no digit appears more than once in any one code number. How many unassigned code numbers are there?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
8个数字选3个不重复的数字有8*7*6=336种方式,所以还剩下336-330=6种密码
小蚊子
C(8,3)A(3,3)-330=6
四个自信
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