8/9 + 5/7 = 56/63 + 45/63 = 101/63 5/6 + 2/3 = 5/6 + 4/6 = 9/6 = 3/2 = 1.5 1/9 + 1/7 = 7/63 + 9/63 = 16/632/5 + 2/3 = 6/15 + 10/15 = 16/15 2/7 + 6/7 = 8/71/2 - 3/7 = 7/14 - 6/14 = 1/141/3 - 2/9 = 3/9 ...