Question:
The number of ways in which the letters of the word ARTICLE can be arranged so that even places are always occupied by consonants is
(a) 576
(b) 4C3 × 4!
(c) 2 × 4!
(d) none of these.
Solution:
(a) 576
There are 3 even places in the 7 letter word ARTICLE.
So, we have to arrange 4 consonants in these 3 places in 4P3 ways.
And the remaining 4 letters can be arranged among themselves in 4! ways.
$\therefore$ Total number of ways of arrangement $={ }^{4} P_{3} \times 4 !=4 ! \times 4 !=576$
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.