SOLUTION: Please is there anyone that can help me with this problem. I have look at videos and read my book on this but still can not figure this out. I thought maybe by there being 26 lette

Algebra ->  Permutations -> SOLUTION: Please is there anyone that can help me with this problem. I have look at videos and read my book on this but still can not figure this out. I thought maybe by there being 26 lette      Log On


   



Question 1025726: Please is there anyone that can help me with this problem. I have look at videos and read my book on this but still can not figure this out. I thought maybe by there being 26 letters in the alphabet and 10 numbers I could find it that way. Then I tried by it 7 characters long but that was still wrong.

A computer password is required to be 7 characters long. How many passwords are possible if the password requires 1 letter(s) and 6 digits (numbers 0-9), where no repetition of any letter or digit is allowed?
There are possible passwords.

Found 2 solutions by Theo, josmiceli:
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
i believe your answer will be as follows.

assuming that the letter is in the first position, then the number of possibilities is:

26 * 10 * 9 * 8 * 7 * 6 * 5

if the letter can be in any position, then multiply that result by 7 because there are 7 positions that the letter can be in.

i get 3931200 assuming the letter has to be in the first position.

i get 7 * 3931200 = 27518400 assuming the letter can be in any position.

hopefully that agrees with what you should be getting.

if not, then let me know what you should be getting and i'll try to figure it out.








Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
For each character of the 7-character password there can be
a different letter or number.
26 letters + 10 digits = 36
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The 1st character can be 36 possible
There are no repetitions, so there are
35 possible for 2nd character
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This continues for 7 characters, so
+36%2A35%2A34%2A33%2A32%2A31%2A30+=+42072307200+
possible passwords
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Hope I got it -you can get other opinions too