15-5=
18-8=
9+9=
17-6=
7+8=
13-2=
14-3=
16-10=
19-2=
12-2=
16-2=
6+6=
10-8=
10-2=
9+8=
5+4=
7+9=
12-10=
16-4=
13+6=
18+2=
12+4=
6-3=
8+8=
7+5=
11-10=
18-7=
14+5=
12+3=
够不够(在合适的里画“√”)
9+3=
7+6=