SOLUTION: You need to have a password with 4 letters followed by 4 even digits between 0 and 9, inclusive. If the characters and digits cannot be used more than once, how many choices do yo

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Question 1094921: You need to have a password with 4 letters followed by 4 even digits between 0 and 9, inclusive. If the characters and digits cannot be used more than once, how many choices do you have for your password?
Answer by math_helper(2461)   (Show Source): You can put this solution on YOUR website!

There are 26 letters for the first letter choice.
25 for the 2nd
24 for the 3rd
23 for the 4th

There are 5 choices for the first digit { 0, 2, 4, 6, or 8 }
4 for the 2nd
3 for the 3rd
2 for the 4th

So there are 26*25*24*23*5*4*3*2 = 43056000 ways (=choices) to make a password this way.

Alt solution: since order is important, we can use the permutation formula P(n,k)= n!/(n-k+1)!.
Viewing it this way, there are P(26,4) ways to pick (arrange) the letters and P(5,4) ways to pick (arrange) the digits: P(26,4)*P(5,4) = 358800*120 = 43056000.

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