11-8=
17-9=
16-7=
3+8-9=
13-5=
13-9=
18-9=
12-5+8=
12-7=
12-8=
17-8=
13-8+6=
16-9=
12-3=
12-9=
4+9-7=
11-7=
16-8=
14-9=
7+7-8=
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