-3/5 - 1/5 = -4/5,
-1/3 - 2/3 = -3/3 = -1,
-3/7 - 4/7 = -7/7 = -1,
-1/4 - 5/7 = -7/28 - 20/28 = -27/28,
-5/6 - 1/3 = -5/6 - 2/6 = -7/6 = -1 1/6,
-1/8 - 3/4 = -1/8 - 6/8 = -7/8,
-4 3/8 - 2 1/4 = -4 3/8 - 2 2/8 = -6 5/8,
-6 1/2 - 3 5/7 = -6 7/14 - 3 10/14 = -9 17/14 = -10 3/14,
-9 - 3 5/9 = -12 5/9