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概率论与数理统计第 6 讲. 本讲义可在网址 http://math.shekou.com 或 ftp://math.shekou.com 下载. 习题 1-3 第 23 题 任取两个真分数 , 求它们的乘积不大于 1/4 的概率 . 解 : 假设这两个真分数取值为 x , y , 每次试验为一对数 ( x , y ), 可用平面上的点表示 :. y. 1. xy =1/4. x. O. 1. 1/4. 因此所求概率为 :. 第二章 随机变量及其分布. - PowerPoint PPT Presentation
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6http://math.shekou.comftp://math.shekou.com
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