10张奖券中含有2张中奖的奖券,每人购买一张,则前4个购买者中恰有1人中奖的概率是( )。A. 0.84 B. 0.1 C. C1040.2x0.83...

作者: tihaiku 人气: - 评论: 0
问题 10张奖券中含有2张中奖的奖券,每人购买一张,则前4个购买者中恰有1人中奖的概率是( )。
选项 A. 0.84 B. 0.1 C. C1040.2x0.83 D. 0.83x0.2
答案 A
解析 提示:中奖的概率P=0.2,该问题是4重贝努利试验,前4个购买者中恰有1人中奖的概率为C410.2x0.83=4x0.2x0.83 =0.84,故应选A。

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