How many words can be formed by arranging the letters of the word ‘INDIA’, so that the vowels are never together?
To find: Number of words that can be formed so that vowels are never together
Number of words such that vowels are never the together = Total number of words - Number of words where vowels are together
Total number of words = 
To find a number of words where vowels are together
Let the vowels I, I, A be represented by a single letter Z
 the new word is NDZ
the new word is NDZ
A number of permutations = 3! = 6
Z is composed of 3 letters which can be permuted amongst themselves.
Number of permutations of Z = 
Number of words where vowels are together =  = 18
 = 18
 Number of words where vowels are not together = 60 - 18 = 42
Number of words where vowels are not together = 60 - 18 = 42
There are 42 words where vowels are not together