-1/3-2/3;-1/8-3-4;-6 1/2-3 5/7
-1/3-2/3 = -3/3 = -1 -1/8-3-4 = -1/8-7 = -7 1/8 -6 1/2-3 5/7 = -6 7/14-3 10/14 = -9 17/14 = -10 3/14
-1/3-2/3=-3/3=-1 -1/8-3-4=-7 1/8 -6 1/2-3 5/7=-13/2-26/7=-91/14-52/14=-10 3/14