In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together? Choose the correct option: A) 520 B) 720 C) 890 D) 870 E) 1098
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.   Required number of ways = (120 x 6) = 720.   ANSWER 720 72
<result>B</result>
In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together?