Question

A password is 6 to 8 characters long, where each character is a lowercase English letter or a digit. How many different passwords are there if the first two characters must be digits

Answer 1

If the first two characters of the password must be digits, there are 10 possible choices for each of the first two characters. After the first two digits, there are 26 possible choices for each of the remaining 4-6 characters. Therefore, the total number of possible passwords is:

10 x 10 x 26 x 26 x 26 x 26 = 45,697,696

So, there are 45,697,696 different passwords that meet the given criteria.