SOLUTION: there are 7 letters which is U,N,I,F,O,R,M. Find the number of different four-letter codes which end with consonant (not repetition)
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-> SOLUTION: there are 7 letters which is U,N,I,F,O,R,M. Find the number of different four-letter codes which end with consonant (not repetition)
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Question 1186305: there are 7 letters which is U,N,I,F,O,R,M. Find the number of different four-letter codes which end with consonant (not repetition) Answer by greenestamps(13200) (Show Source):
The only restriction (other than no repetition) is that the last letter in the 3-letter code must be a consonant. So pick that letter first; there are 4 choices.
Then pick the other three letters of the code (in any order). There are 6 choices for the second letter you choose, 5 for the third, and 4 for the last.
By the fundamental counting principle, the number of 4-letter codes with no repetition of letters and the last letter a consonant is 4*6*5*4 = 480.
