12-92 13-85 98-2525+30
24-424-20 56+3939+56 57-3475-34
15-7= 20+35= 17-9= 63-9=
80-8= 62+30= 20+40= 51+6=
①5+46=
②72+19=
③85-17=
④27+63=
⑤90-28=
⑥65-59=