解：?$(1)(46-40) +(36-40 ) +(38-40) =0$?
?$(2)$?數(shù)據(jù)：?$1、$??$1、$??$2、$??$3$?
平均數(shù)為?$1.75$?
?$(1-1.75) +(1-1.75) +(2-1.75) +(3-1.75) =0$?
?$(3 ) (a-m) +(b-m) +(c-m) +(d-m) +(e-m) =0$?
驗(yàn)證?$： (a-m) +(b-m) +(c-m) +(d-m) +(e-m )$?
?$ =(a+b+c+d+e ) -5m=0$?
