Answer:
See the diagram below:
Red 3/8 -----------------> Red-Red = 4/9*3/8 = 1/6
Red 4/9 <
Orange 5/8 --------------> Red-Orange = 4/9*5/8 = 5/18
Red 4/8 --------------------> Orange-Red = 5/9*4/8 = 5/18
Orange 5/9 <
Orange 4/8 ----------------> Orange-Orange = 5/9*4/8 = 5/18