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为了从甲、乙、丙、丁四位同学中选派两位选手参加数学竞赛,老师对他们的五次数学测验...
为了从甲、乙、丙、丁四位同学中选派两位选手参加数学竞赛,老师对他们的五次数学测验成绩进行统计,得出他们的平均分均为85分,且S甲2=100、S乙2=110、S丙2=120、S丁2=90.根据统计结果,派去参加竞赛的两位同学是( )
A.甲、乙
B.甲、丙
C.甲、丁
D.乙、丙
考点分析:
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