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प्रश्न
In how many ways can the letters of the word 'STRANGE' be arranged so that
the vowels never come together?
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उत्तर
Total number of words that can be made with the letters of the word STRANGE = 7! = 5040
Number of words in which vowels always come together = 1440
∴ Number of words in which vowels do not come together = 5040\[-\]1440 = 3600
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