Answer :
[tex]26\cdot26\cdot10\cdot10\cdot10\cdot10\cdot10=\\
26^2\cdot10^5=\\
676\cdot 10000=\\
67600000[/tex]
The first letter can be any one of 26 letters. For each one . . .
The second letter can be any one of 26 letters. For each one . . .
The first digit can be any one of 10 digits. For each one . . .
The second digit can be any one of 10 digits. For each one . . .
The third digit can be any one of 10 digits. For each one . . .
The fourth digit can be any one of 10 digits. For each one . . .
The fifth digit can be any one of 10 digits.
The total number of possibilities is
(26 x 26 x 10 x 10 x 10 x 10 x 10) =
( 26² x 10⁵) = (676 x 100,000) = 67,600,000 .
