<PRE><B>Question 330386</B>
&lt;br&gt;This problem involves some statistical reasoning and knowledge, but there is a very simple solution to it.&lt;br&gt;

We know that there are 10 digits, and 26 letters available.  We can repeat digits, but not letters, thus our password should look something like this, where N is a number, and L is a letter:&lt;br&gt;

NNNLLL&lt;br&gt;

Then we will fill in the number of choices available for each character in the password:&lt;br&gt;

10*10*10*26*25*24&lt;br&gt;

When we multiply these numbers out, we will have the total number of possible passwords:&lt;br&gt;

15,600,000&lt;br&gt;

There are 15,600,000 possible passwords based on the given criteria.&lt;br&gt;

As a bonus, if we were not allowed to repeat digits, then we would have:&lt;br&gt;

10*9*8*26*25*24 or 11,232,000 possible passwords.&lt;br&gt;

There is a whole lot more to this subject, but I hope this helps you get started!  :)</PRE>