10 + 10
20
0-1=
1
8 - 4 =
4
20 - 5 =
15
2 + 6
8
10 + 5=
20 +10 =
30
3 +8 =
11
5 + 6 =
17 -7=
10
10 + 4 =
14
13 + 6
19
30 -5 + 3
28
11 + 6
17
20 + 15=
35