5/6 - 3/4 = 10/12 - 9/12 = 1/121/3 + 1/5 = 5/15 + 3/15 = 8/153/10 + 1/2 = 15/50 + 25/50 = 40/50 = 4/51/3 - (-1/7) = 1/3 + 1/7 = 7/21 + 3/21 = 10/219/20 + 3/8 = 36/80 + 30/80 = 66/80 = 33/4019/75 - 11/50 = 38/150 - 33/150 = 5/150 = 1/3013/50 - 17/75 = 39/150 - 34/150 = 5/150 = 1/3011/14 + 8/21 = 33/42 + 16/21 = 33/42 + 32/42 = 65/42 = 5/6
5/6 - 3/4 = 10/12 - 9/12 = 1/12
1/3 + 1/5 = 5/15 + 3/15 = 8/15
3/10 + 1/2 = 15/50 + 25/50 = 40/50 = 4/5
1/3 - (-1/7) = 1/3 + 1/7 = 7/21 + 3/21 = 10/21
9/20 + 3/8 = 36/80 + 30/80 = 66/80 = 33/40
19/75 - 11/50 = 38/150 - 33/150 = 5/150 = 1/30
13/50 - 17/75 = 39/150 - 34/150 = 5/150 = 1/30
11/14 + 8/21 = 33/42 + 16/21 = 33/42 + 32/42 = 65/42 = 5/6