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某单位员工按年龄分为A,B,C三组,其人数之比为5:4:1,现用分层抽样从总体中...
某单位员工按年龄分为A,B,C三组,其人数之比为5:4:1,现用分层抽样从总体中抽取一个容量为20的样本,已知甲被抽到的概率是
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,则在C组中应有员工
人.
考点分析:
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