If there are $26$ available capital letters and $6$ available numbers $0$ to $9$ to complete a $6$ "digit" combination (a license plate for example) what is the formula for calculating the number of possible combinations? I am not a math major nor do i understand all the symbols you guys use, the simplest equation or maybe just the answer will be appreciated... THANKS!!
Calculating license plate combinations
2 Answers
You multiply the choices at each position. If each position can have all $36$ possibilities, you have $36^6=2,176,782,336$ plates available. If you require that the first three positions be letters and last three be numbers (a common pattern) it is $26^3\cdot 10^3=17,576,000$
That's a start... but you're forgetting the possibility of vanity plates, plates with 7 characters or 5 characters or even fewer, and obscene plates.
In the United States, I've seen many license plates with any number of characters between 1-7. The DMV also won't approve obscene vanity plates, so you have to subtract an arbitrary guess of the number of obscene plates from your final total (say, 50,000).
So your total would be something like the following:
[(36) + (36*36) + (36*36*36) + (36*36*36*36) + (36*36*36*36*36) + (36*36*36*36*36*36) + (36*36*36*36*36*36*36)] - 50,000
Edit: just noticed your qualifier, limiting you to six characters. Sorry, just trying to answer it realistically