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Combination and Permutation Question

Consider the letters of the word MONDAY. How many permutations of 4 different letters can be chosen if:
2 vowels cannot be together?

Not sure if my logic is correct:
Calculate all permutations (6P4) - No vowel Perms(4P2) * six ways 2 vowels can be together (=6).
This gives me 288 which is the correct answer.

Is this the only way to get the correct answer or is there any way to do this using positive logic?
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Original post by xlaser31
Consider the letters of the word MONDAY. How many permutations of 4 different letters can be chosen if:
2 vowels cannot be together?

Not sure if my logic is correct:
Calculate all permutations (6P4) - No vowel Perms(4P2) * six ways 2 vowels can be together (=6).
This gives me 288 which is the correct answer.

Is this the only way to get the correct answer or is there any way to do this using positive logic?

No vowels + 2*One vowel chosen + Two vowels (not together) and two consonants
4P4 + 2*4P1*4P3 + 3P2*4P2
Your way is simpler.

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