17-8= 36+3= 46-4= 72+8=
40+60= 20-7= 58+4= 89-8=
67+8= 100-10+6= 27-9+10= 68-(20+30)=
5+8=
4+7=
6+9=
12-10=
8+8=
18-3=
5+7=
6+11=
3+9=
5+9=
12-8=
11-6=
根