In how many different ways can the letters of the word 'BANKING' be arranged so that the vowels always come together ? Choose the correct answer.
A) 740
B) 720
C) 800
D) 550
E) 690
In the word 'BANKING', we treat the two vowels AI as one letter. Thus,we have BNKNG (AI)   This has 6 letters of which N occurs 2 times and the rest are different.   Number of ways of arranging these letters= 6!/(2!)(1!)(1!)(1!)(1!)=360.   Now 2 vowels AI can be arranged in 2!=2 ways.   Required number of ways =(360*2)= 
<gadget id="calculator">(360*2)</gadget>
<output>720</output>
720.   Answer is 720
<result>B</result>
In how many different ways can the letters of the word 'BANKING' be arranged so that the vowels always come together ?