Firstly, we have to find the LCD, or lowest common denominator, of 1/9 and 2/3. We can find this by listing all the multiples of 9 and 3. In this case, the LCM is 9. Multiply 1/9 by 1/1 and 2/3 by 3/3:
Now subtract 1/9 from 6/9:
Now subtract 5/9 from 7/9 and your answer will be