a = 5/6 + .../3 = 3/2
a = 5/6 + .../3 = 9/6
a = .../3 = 9/6 - 5/6
a = .../3 = 4/3
a = 4
b = 12/7 - 3/... = 27/28
b = 48/28 - 3/... = 27/28
b = 48/28 - 27/28 = 3/...
b = 21/28 = 3/...
b = 3/4 = 3/...
b = 4
c = 11/5 + .../... = 47/15
c = 47/15 - 33/15 = .../...
c = 14/15
d = 9/4 + .../... = 6/7
d = 63/28 - 24/28 = .../...
d = 39/28