Question

The number of different words which can be formed from the letters of the word LUCKNOW when the vowels always occupy even places is

• A. $120$
• B. $720$
• C. $400$
• D. None of these

Answer 1

The correct option is B

$720$

Explanation for the correct option:

Find the required number of words.

The word 'LUCKNOW' is given.

In the given word there are $2$ vowels $o,u$ and there are three even places.

The number of word formed in which vowel occupies the even places is given by ${}^{3}C_2·2!·5!=720$.

Therefore, the number of different words in which vowel occupies the even places is $720$.

Hence, option $B$ is the correct answer.