How many passwords are there if a password must be 5 characters long and the characters must be lower case letters.
If repeats are allowed then you have 5^26=1.49 X 10^18
If the order of the letters doesn't matter, then nPr(26,5)=7,893,600
If the order of the letters matter, then, nCr(26,5)=65,780
+118723 There are 26 choices for each of the 5 positions so it will be
26*26*26*26*26 = 26^5 = 11 881 376 = 1.1881376 * 10^7
+118723
Also guest you have your permutation and combinations muddled up.
If the letters all must be different then
If order doesn't matter then the answer will be smaller and you use C (for combinations)
If order does matter then the answer will be bigger and you use P (for permutations)
If you swap your answers around then they will be correct. :)
