1.85﹣+= 1÷×= +0.375=
2.4﹣= (+)×2.4= 5÷×5÷=
10×45%= 1.25×8= 40×(1﹣20%)=
①47×75%+53×
②1.25×3.2×0.25
③3- ÷ -
④ ÷[ ×( - )]
①0.83+1.675 ②756+1328 ③+ ④57%+