Question
Mathematics Question on permutations and combinations
If all the words with or without meaning made using all the letters of the word "NAGPUR" are arranged as in a dictionary, then the word at 315th position in this arrangement is
A
NRAGUP
B
NRAGPU
C
NRAPGU
D
NRAPUG
Answer
NRAPGU
Explanation
Solution
Arranging the letters in alphabetical order: NAGPUR
Starting with A: 5!=120 positions
Starting with G: 5!=120 positions, cumulative: 240
Starting with N and A: 4!=24 positions, cumulative: 264
Starting with N and G: 4!=24 positions, cumulative: 288
Starting with N and P: 4!=24 positions, cumulative: 312
Now, starting with N, R, and A:
NRAGUP=1, cumulative: 313
NRAGPU=1, cumulative: 314
NRAPGU=1, cumulative: 315
Thus, the word at the 315th position is NRAPGU.