2 1/3. First, you have to find a common denominator. The common denominator is 6. Whatever you multiply to the bottom you have to do to the top. So, 3 1/2 is equal to 3 3/6. You subtract 3 3/6 and 1 1/6 and you get 2 2/6. You can simplify and you get 2 1/3
