11/6-1/3 = 9/6 should be equivalent
This is given by the multinomial coefficient:

If you're not familiar with the multinomial coefficient, you may be able to see it more clearly if you count the number of possible combinations taking each distinct letter

times, where

is the number of times it shows up in the original word.
ANSWER: x = 1/3
WORKING OUT:
2 times x times 3 = 2
6 times x = 2
x = 1/3