How many 3-letter "words" can be formed from the standard 26-letter alphabet, if the first letter must be a vowel (A, E, I, O, or U)? (We aren't necessarily talking about English words; something like EQX is perfectly valid here.)
There are 5 choices for the first letter, then 26 choices for the second letter, then 26 choices for the third letter.
so total number of possible words = 5 * 26 * 26 = 3380