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)