SOLUTION: John, Trey, and Miles want to know how many two-letter secret codes there are that don't have a repeated letter. For example, they want to count BA and AB, but they don't want to c

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Question 914412: John, Trey, and Miles want to know how many two-letter secret codes there are that don't have a repeated letter. For example, they want to count BA and AB, but they don't want to count doubles such as ZZ or XX. John says there are 26+25 because you don't want to use the same letter twice; that's why the second number is 25. Trey says he thinks it should be times, not plus: 26x25. Miles says the number is 26x26-26 because you need to take away the double letters. Discuss the boys ideas. Which answers are correct, which are not, and why?
Answer by CubeyThePenguin(3113) About Me  (Show Source):
You can put this solution on YOUR website!
There are 26 choices for the first letter.
There are 25 choices for the second letter. (Can't be the same as the first)

Trey is correct.