Question:
Words with or without meaning are to be formed using all the letters of the word EXAMINATION. The probability that the letter $M$ appears at the fourth position in any such word is:
Correct Option: , 2
Solution:
AAEIIMNNOTX
Total words with $\mathrm{M}$ at fourth Place $=\frac{10 !}{2 ! 2 ! 2 !}$
Total words $=\frac{11 !}{2 ! 2 ! 2 !}$
Required probability $=\frac{10 !}{11 !}=\frac{1}{11}$