①12+3-7=
②15-6-3=
③11-6-3=
④8+2+5=
⑤14-2-7=
⑥13-8+4=
11-7= 9+30= 26-6= 46+4+2=
75+20= 14-9= 90-10= 88-8+6=
9+9= 58-50= 15-6= 23+(49-9)=
①x:3=:
②=
③:=:x
④:x=3:12
⑤:x=5%:0.6
⑥=