5/12 - 1/12 = 4/12 = 1/37/15 - 11/15 = -4/155/16 - 1/16 = 4/16 = 1/4-5/6 + 2/3 = -10/12 + 8/12 = -2/12 = -1/6-3/4 - 4/5 = -15/20 - 16/20 = -31/20-1/2 + 1/8 = -4/8 + 1/8 = -3/8
5/12 - 1/12 = 4/12 = 1/3
7/15 - 11/15 = -4/15
5/16 - 1/16 = 4/16 = 1/4
-5/6 + 2/3 = -10/12 + 8/12 = -2/12 = -1/6
-3/4 - 4/5 = -15/20 - 16/20 = -31/20
-1/2 + 1/8 = -4/8 + 1/8 = -3/8