The letters of the word ‘SURITI’ are written in all possible orders, and these words are written out as in a dictionary. Find the rank of the word ‘SURITI’.
Given the word SURITI.
Arranging the permutations of the letters of the word SURITI in a dictionary:
To find: Rank of word SURITI in dictionary.
First comes, words starting with letter I = 5! = 120
words starting from letter R = 5!/2! = 60
words starting from SI = 4! = 24 (4 letters no repetation)
words starting from SR = 4!/2! = 12 (4 letters, one repetation of I)
words starting from ST = 4!/2! = 12 (4 letters, one repetation of I)
words starting from SUI = 3! = 6 (3 letters no repetation)
words starting from SUR; SURIIT = 1
SURITI = 1
Rank of the word SURITI = 120 + 60 + 24 + 12 + 12 + 6 + 1 + 1
= 236
Hence the rank of the word SURITI in arranging the letters of SURITI in a dictionary among its permutations is 236.