328+199= 2.4+3.06= 24×12.5%= 4﹣﹣=
﹣= 3.2÷0.01= 3.5:1.4=﹣=
①17.8﹣4.6﹣5.4
②79×101
③( + - )÷
④ ×25%+ ×0.25
①3.9×2.5×4
② ÷[ ×( - )]
③ × + ÷
改正: