I think it in right forum. It's in university, but title of class is Basic Statistic.
I'm supposed to find out how many three-letter combinations i can make using the US alphabet. letters can be repeated...
so, it's from AAA to ZZZ
I not sure where to begin problem. answer in book: 18,278
i though it was , but it not answer.
thank you!
Hello, berto!
How many three-letter combinations can be made using the US alphabet.
Letters can be repeated.
Answer in book: 18,278
I agree with Plato . . . check the original wording.
I bet it says "combinations with up to three letters".
Then the answer is: .