①-÷-
②×+÷8
③(×27-)×
④÷[(+)×]
①-+-
②×+÷
③(6﹣1.3×4)÷0.1
④0.4×0.25×8×125
⑤3.4÷[(1.25+0.45)×23]
①6.4×2.5×1.25
②8.5×98%
③÷4+×
④×
①273﹣73﹣27
②1.25×9.78×80
③()×24
④[1﹣()]÷