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Question
How many words (with or without dictionary meaning) can be made from the letters in the word MONDAY, assuming that no letter is repeated, if all letters are used but first is vowel.
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Solution
A or O has to be placed in the first position. This can happen in two ways.
Remaining 5 places 5! = can be filled in 120 ways.
Number of words which start with vowel = 2 x 120 = 240.
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