The Greek alphabet contains 24 letters. How many fraternity names with Greek letters can be formed if each fraternity name contains 3 letters and repetition of letters is not permitted?
For the first letter we have 24 choices. Since letters can't repeat the second letter has 23 choices (24 minus 1 that was used for the first slot) and the third has 22 (24 minus one for the first slot and one for the second slot).
The total number of combinations is thus: [tex] 24 \times 23 \times 22 = 12,144 [/tex]
