Actually, there are only ten possible numbers per digit and we have 5 digits, 0, 1, 2, 3, 4, 5, 6, 7 , 8, 9.We have 2 slots for letters and there are 26 letters (I hope you know them :))The combination of numbers and letters? 10*10*10*10*10*26*26, 5 tens from the numbers, 2 twenty sixes from the letters. Answer:67,600,000 possibilities.Of course, I'm no math whiz, and this might not be the right answer. I recommend checking with a person who is good at this.Cheers.