80道脱式计算 答案过程题目借鉴.docx

1、80道脱式计算 答案过程题目借鉴1.25（8+10） =1.258+1.2510 =10+12.5=22.5 9123-（123+8.8） =9123-123-8.8 =9000-8.8 =8991.2 1.248.3+8.31.76 =8.3（1.24+1.76) =8.33=24.9 99991001 =9999（1000+1） =99991000+99991 =10008999 14.86.3-6.36.58.33.7 =（14.8-6.5）6.38.33.7 =8.36.3+8.33.7 8.3（6.33.7） =8.310 =83 1.24+0.78+8.76 =（1.24+8.76

2、）+0.78 =10+0.78 =10.78 933-157-43 =933-（157+43） =933-200 =733 4821-998 =4821-1000+2 =3823 I3212525 =4812525 =（425）（8125） =1001000 =100000 9048268 =（2600+2600+2600+1248）26 =260026+260026+260026+1248269 =100+100+100+48 =348 2881 43 =（1290+1591） 434 =129043+159143 =30+37 3.242.33.75-12.50.42316 =3.242.33.75-1.2542.31.6 =42.3(3.23.75-1.251.6) =42.3(40.83.75-1.2540.4) =42.3(40.423.75-1.2540.4) =42.3(4x0.4x7.5-1.25x4x0.4)