10+5=
15
10-9=
1
1+___=3
2
7+7=
14
9-3=
6
5+____= 9
4
12+2=
20-10=
10
1+___= 9
8
15+5=
20
19-9=
____+8= 15
7
20+0=
20-7=
13
10+___=19
9
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