1.	3 - 1 = 2	13 - 6 = 7	10 - 2 = 8	9 - 7 = 2	3 - 2 = 1
2.	14 - 5 = 9	7 - 3 = 4	5 - 4 = 1	16 - 9 = 7	15 - 6 = 9
3.	16 - 8 = 8	12 - 4 = 8	15 - 6 = 9	14 - 8 = 6	9 - 5 = 4
4.	7 - 2 = 5	12 - 9 = 3	11 - 3 = 8	14 - 7 = 7	2 - 1 = 1
5.	11 - 8 = 3	10 - 8 = 2	3 - 3 = 0	12 - 8 = 4	12 - 6 = 6
6.	4 - 3 = 1	8 - 7 = 1	10 - 6 = 4	11 - 6 = 5	13 - 5 = 8
7.	7 - 1 = 6	4 - 0 = 4	10 - 4 = 6	15 - 9 = 6	7 - 0 = 7
8.	13 - 5 = 8	9 - 8 = 1	8 - 4 = 4	8 - 4 = 4	17 - 9 = 8
9.	8 - 5 = 3	13 - 8 = 5	4 - 2 = 2	17 - 8 = 9	5 - 1 = 4
10.	4 - 3 = 1	7 - 5 = 2	12 - 6 = 6	12 - 3 = 9	13 - 8 = 5
11.	8 - 3 = 5	11 - 5 = 6	10 - 8 = 2	15 - 8 = 7	10 - 9 = 1
12.	10 - 2 = 8	8 - 7 = 1	4 - 1 = 3	13 - 4 = 9	17 - 9 = 8
13.	8 - 1 = 7	7 - 4 = 3	3 - 2 = 1	10 - 1 = 9	6 - 4 = 2
14.	14 - 9 = 5	1 - 0 = 1	4 - 1 = 3	12 - 5 = 7	4 - 0 = 4
15.	12 - 7 = 5	12 - 9 = 3	10 - 3 = 7	10 - 9 = 1	15 - 7 = 8
16.	11 - 2 = 9	6 - 5 = 1	9 - 4 = 5	9 - 2 = 7	3 - 0 = 3
17.	8 - 2 = 6	7 - 3 = 4	11 - 5 = 6	8 - 1 = 7	13 - 7 = 6
18.	6 - 3 = 3	9 - 7 = 2	15 - 9 = 6	5 - 2 = 3	9 - 1 = 8
19.	7 - 6 = 1	9 - 5 = 4	14 - 8 = 6	5 - 3 = 2	18 - 9 = 9
20.	9 - 4 = 5	7 - 4 = 3	5 - 4 = 1	6 - 3 = 3	11 - 6 = 5

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