3 4/5 - 2 3/5 = 1 1/5
7 5/6 - 4 2/3 = 3 + (5-4)/6 = 3 1/6
4 5/6 - 2 5/12 = 2 + (10-5)/12 = 2 5/12
10 4/9 - 8 5/18 = 2 + (8-5)/18 = 2 3/18 = 2 1/6
9 1/2 - 2 1/4 = 7 + (2-1)/4 = 7 1/4
6 3/4 - 2 2/3 = 4 + (9-8)/12 = 4 1/12
11 3/7 - 5 1/3 = 6 + (9-7)/21 = 6 2/21
8 3/5 - 6 3/10 = 2 + (6-3)/10 = 2 3/10