Permutations And Combinations Question 304

Question: The number of words that can be formed out of the letters of the word ARTICLE so that the vowels occupy even places is [Karnataka CET 2003]

Options:

A) 36

B) 574

C) 144

D) 754

Show Answer

Answer:

Correct Answer: C

Solution:

  • Out of 7 places, 4 places are odd and 3 even. Therefore 3 vowels can be arranged in 3 even places in $ ^{3}P_3 $ ways and remaining 4 consonants can be arranged in 4 odd places in $ ^{4}P_4 $ ways. Hence required no. of ways = $ ^{3}P_3 $ × $ ^{4}P_4 $ = 144.