M4maths Previous Puzzles

14 Sep 2012 rank

rank of the word INDIA in the dictionary of words formed by the letters of the word INDIA.

OPtion

1) 46
2) 47
3) 48
4) 49
5) 50
6) 51
7) 52
8) 53
9) 54
10) none of these

Solution

INDIA, total no. of words = 5*4*3*2*1/2*1 = 60
arranged letters A D I I N
first letter I, before it there are 2 letters so [60/5]*2
second letter N, before it 3 letters so [12*2/4]*3 (2 is for revision of I)
third letter D, before it 1 letter so [6/3]*1
fourth letter I, before it 1 letter so [2/2]*1
so rank = [60/5]*2 + [12*2/4]*3 + [6/3]*1 + [2/2]*1 + 1 = 24+18+2+1+1 = 46

Correct Option: 1 Best Solution (0)