A password consists of 2 letters followed by 2 digits. How many different passwords can be formed?

Solution:

The problem is an example of arrangement or permutations. The password comprises 2 letters and 2 digits with digits following the letter. We assume that letters and digits can be repeated.

Letter 1 Letter 2 Digit 2 Digit 2

Since there are 26 letters in the English alphabet the first position can be filled in 26 ways considering the alphabet from a to z. Similarly, the second position of the password can be filled in 26 ways.

The third component of the password can be filled in 10 ways and even the fourth position of the digit can be filled in 10 ways (digits 0 to 9).

The number of different passwords that can be formed thus is:

26 × 26 × 10 × 10 = 67600 ways

A password consists of 2 letters followed by 2 digits. How many different passwords can be formed?

Summary:

A password consists of 2 letters followed by 2 digits. The number of different passwords (2 letters followed by 2 digits) that can be formed is 67600.