SOLUTION: In how many ways can a 4-digit code be arranged using 1,2,3,4,5,6,7,8 and 9

Question 1207713: In how many ways can a 4-digit code be arranged using 1,2,3,4,5,6,7,8 and 9
Answer by ikleyn(52793) (Show Source): You can put this solution on YOUR website!
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In all, there are 9 digits from 1 to 9 inclusive.



If repetition is not allowed, then the number of different 4-digit codes is 

    9*8*7*6 = 3024.



If repetition is allowed, then the number of different 4-digit codes is 

    9*9*9*9 =  = 6561.

Solved.

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As the problem is worded/printed in the post, it is a " lame horse ",
since it does not specify if repetition is allowed or not.

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