You turn 8 5/6 and 2 1/3 into improper fractions (8 5/6 becomes 53/6 and 2 1/3 becomes 7/3)
Then you take 53/6 and 7/3 and find a common denominator which is 6
Then you multiply 7x2 and 3x2 which equals to 14/6
53/6 - 14/6 is 39/6
You can leave it as 39/6 or change it into a mixed number, if you make it a mixed number then you would get 6 3/6 which is equivalent to 6 1/2.