82-40.5÷0.81×1.2=82-(40.5×1)+(40.5×0.2)÷0.81=82-(40.5+8.1÷0.81)=82-(40.5+10=82-50.5=31.5
这题没什么简算，按步骤就好原式=82-50x1.2=82-60=22望采纳，谢谢
脱式计算82一40.5÷0.81×1.2=82-50x1.2=82-60=22
