3/5 + 1/4 = 12/20 + 5/20 = 17/20
5/8 + 3/4 = 10/16 + 12/16 = 22/16 = 11/8
3/8 - 1/6 = 9/24 - 4/24 = 5/24
15/16 - 5/12 = 45/48 - 20/48 = 25/48
1/2 + 1/3 - 1/6 = 3/6 + 2/6 - 1/6 = 4/6 = 2/3
3/4 - 5/8 + 11/12 = 18/24 - 15/24 + 22/24 = 25/24
7/8 + 1/3 - 3/8 = 21/24 + 8/24 - 9/24 = 20/24 = 5/6
7/15 - (2/3 - 3/5) = 7/15 - (10/15 - 9/15) = 7/15 - 1/15 = 6/15 = 2/5
0,25 + 5/7 - 3/4 = 25/100 + 5/7 - 3/4 = 1/4 + 5/7 - 3/4 = 7/28 + 20/28 - 21/28 = 6/28 = 3/14
9/16 - (0,125 + 1/4) = 9/16 - ( 125/1000 + 1/4) = 9/16 - (1/8 + 1/4) = 9/16 - (1/8 + 2/8) = 9/16 - 3/8 = 9/16 - 6/16 = 3/16