Question
A three-letter word is to be formed such that the first
and last letters are consonants and the middle letter is a vowel. How many such words can be formed?Solution
ATQ, Number of ways to choose the first letter (consonant) 21C1 = 21 Number of ways to choose the second letter (vowel) = 5C1 = 5 Number of ways to choose the third letter (different vowel) = 21C1 = 21 (Since it must be different from the first vowel) Hence total number of ways = 21 × 5 × 21 = 2205 ways
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