Question

In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together?

• A. 120
• B. 720
• C. 4320
• D. 2160
• E. None of these

Answer 1

The correct option is B 720

The word 'OPTICAL' contains 7 different letters.
When the vowels OIA are always together, they can be supposed to form one letter.
Then, we have to arrange the letters PTCL (OIA).
Now, 5 letters can be arranged in 5! = 120 ways.
The vowels (OIA) can be arranged among themselves in 3! = 6 ways.
$\therefore$ Required number of ways = (120 x 6) = 720.