3+0=
3+2=
4+1=
5-4=
5-5=
5-2=
0+4=
3+1=
4-2=
3-1=
0+5=
2-2=
4+913 19-614 7+412
1517-3 14+620 17-79
86 4+04 10﹣56
79 9﹣53 17﹣77
①5.8﹣1.9﹣2.1
②×2.5××4
③÷(﹣)×
④83×0.75+17÷