A: 2/5 - 1/3 1/6 + 5/12 5/9 - 4/27 1/8 + 3/8 7/10 - 1/2 7/12 + 1/2 2/7 + 5/14 11/15 - 2/5 5/6 - 1/6 1/6 + 3/5 3/4 - 2/5 1/3 + 5/12 5/8 - 3/16 1/10 +7/10 9/17 + 8/17 20

2/5 - 1/3 = 6/15 - 5/15 = 1/15

1/6 + 5/12 = 2/12 + 5/12 = 7/12

5/9 - 4/27 = 15/27 - 4/27 = 14/27

1/8 + 3/8 = 4/8

7/10 - 1/2 = 7/10 - 5/10 = 2/10

7/12 + 1/2 = 7/12 + 6/12 = 13/12

2/7 + 5/14 = 4/14 + 5/14 = 9/14

11/15 - 2/5 = 11/15 - 6/15 = 5/15

5/6 - 1/6 = 4/6

1/6 + 3/5 = 5/30 + 18/30 = 13/30

3/4 - 2/5 = 15/20 - 8/20 = 7/20

1/3 + 5/12 = 4/12 + 5/12 = 9/12

5/8 - 3/16 = 10/16 - 3/16 = 7/16

1/10 +7/10 = 8/10

9/17 + 8/17 = 17/17

11/15
7/12
11/27
1/2
1/5
1 целая 1/12
9/14
1/3
2/3
23/30
1 целая 3/20
3/4
7/16
4/5
1