.
x 甲=
1
7 (45+44+66)=51;
x 乙=
7 (48+44+60)=51;
S甲2=
7 [(45-51)2+(44-51)2+(66-51)2]=65;
S乙2=
7 [(48-51)2+(44-51)2+(60-51)2]=27;
∵S甲2>S乙2,
∴乙种水果销售更稳定.