Find the number of words formed by permuting all the letters of the following words :
INDIA
Since we know, Permutation of n objects taking r at a time is nPr,and permutation of n objects taking all at a time is n!
And, we also know Permutation of n objects taking all at a time having p objects of the same type, q objects of another type, r objects of another type is . i.e. the, number of repeated objects of same type are in denominator multiplication with factorial.
Given, the word INDIA. It has 5 letters, and it has 1 repeated letter ‘I.’ The letter I is repeated twice and all other letters are distinct.
The problem can now be rephrased as to find a total number of permutations of 5 objects (I, N, D, I, A) of which two objects are of same type (I, I).
Total number of such permutations
= 60
Hence, a total number of permutations of the word INDIA is 60.