(1-×10)]×
18×-
37×+6.4×7.5-
2020×
+×
×99+
14×(+)×18
①
②18×()
③(99+)÷9
④0.75×
①273﹣73﹣27
②1.25×9.78×80
③()×24
④[1﹣()]÷
①6.4×2.5×1.25
②8.5×98%
③÷4+×
④×