求计算过程

更新时间2018-08-08 16:50:49

(15%-9%)^2*0.2+(10%-9%)^2*0.6+(0-9%)^2*0.2=0.0024怎么算

解答：（15%-9%）^2*0.2+(10%-9%)^2*0.6+(0%-9%)^2*0.2

       =    6%^2*0.2+1%^2*0.6+9%^2*0.2

       =(6^2+1^2*3+9^2)*(1%^2*0.2)

       =(36+3+81)*(0.00002)

       =120*(0.00002)

       =0.00024