Question
A three-letter word is to be formed using the English
alphabet where the first letter is a vowel, the second letter is a vowel different from the first, and the third letter is a consonant. How many such words can be formed?Solution
ATQ, Number of ways to choose the first letter (vowel) 5C1 =5 Number of ways to choose the second letter (Different vowel) = 4C1 = 4 Number of ways to choose the third letter (consonant) = 21C1 = 21 Hence total number of ways = 5 × 4 × 21 = 420 ways
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