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प्रश्न
How many permutations can be formed by the letters of the word, 'VOWELS', when
each word begins with O and ends with L?
उत्तर
If we fix the first letter as O and the last letter as L, the remaining 4 letters can be arranged in 4! ways to form the words.
∴ Number of words that start with O and end with L = 4! = 24
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