①80%x﹣0.4×1.2=1.2
②(27.5﹣3.5)÷x=4
③4:(1﹣x)=
④
1.25×0.08=
+1=
6.97﹣1.09=
+=
5+3﹣5+3=
﹣=
3.34×99+3.34=
①x-x=
②:x=:
③x+45×=12