共30题用时5分钟
36+45=
28-19-9=
51-18=
39-27=
3+14+7=
52-16=
61-15=
82-36=
25-7-13=
56-38=
37+48=
26-17-5=
3+29=
15+3+10=
46+14=
82-34=
12+15+2=
75-46=
60-25=
26-18-8=
54-26=
80-9=
19-8+11=
38+27=
9+34=
30-8-16=
62-38=
18+26=
30-13-8=