There are 26 ways the first letter can be. For each of those 26 ways, there are 26 ways the second letter can be. That's 26×26 ways the first and second letters can be. For each of those 26×26 ways, there are 26 ways the third letter can be. That's 26×26×26 ways the first, second and third letters can be. For each of those 26×26×26 ways, there are 26 ways the last letter can be. That's 26×26×26×26 ways the first, second, third and last letters can be. So we multiply 26×26×26×26 and get 456,976. So there's just 1 way to get EAFC out of all those 456,976. So the probability is 1 out of 456,876 or 1/456,976 Edwin