How many 3-letter words can be formed out of the letters of the word `CORPORATION`, if repetition of letters is not allowed?
990
336
720
504
Explanation:
There are in all 11 letters in the word `CORPORATION`.
Since, Repetition is not allowed, there are 8 different letters that can be used to form 3-letter word.
Therefore, total number of words that can be formed = 8P3 = (8 $\times$ 7 $\times$ 6) = 336.