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

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