9﹣0.99= 24÷=
2022÷2021= -=
135+398= 5﹣0.5= 0.24×50= 2﹣2÷7=
÷2= 1.25×9×8= += (+)×72=
728﹣299= 0.23= 3.6×25%= 6÷=
8﹣1.3﹣1.7=
①36×()
②1.3×37.5%+2.7×
③ [()]
④13÷()×