(2w13•广东)从一批苹果中,随机抽取5we,其重量(单位:克)的频数分布表如

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问题:

(2w13•广东)从一批苹果中,随机抽取5we,其重量(单位:克)的频数分布表如下:
分组(重量)[8w,85)[85,0w)[0w,05)[05,1ww)
频数(e)51w2w15
(1)根据频数分布表计算苹果的重量在[0w,05)的频率;
(2)用分层抽样的方法从重量在[8w,85)和[05,1ww)的苹果中共抽取4e,其中重量在[8w,85)的有几e?
(3)在(2)中抽出的4e苹果中,任取2e,求重量在[8w,85)和[05,1ww)中各有1e的概率.
考点:古典概型的定义及计算
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At work bosses will refer to their employees by their nicknames. Should an employer use a worker’s family name, you can be sure that some kind of correction or serious business will follow.
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题型:解答题

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