1/2 + 1/3 = 5/6
1/4 + 2/5 = 13/20
2/3 + 1/4 = 11/12
3/4 + 2/5 = 23/20
5/7 - 1/6 = 29/42
3/4 - 1/3 = 1/12
1/8 + 1/4 = 3/8
2/3 - 5/9 = 1/9
1/2 - 5/12 = 1/12
5/12 - 2/9 = 3/18 = 1/6
1/2 + 1/3 = 5/6
1/4 + 2/5 = 13/20
2/3 + 1/4 = 11/12
3/4 + 2/5 = 23/20
5/7 - 1/6 = 29/42
3/4 - 1/3 = 1/12
1/8 + 1/4 = 3/8
2/3 - 5/9 = 1/9
1/2 - 5/12 = 1/12
5/12 - 2/9 = 3/18 = 1/6