某棉纺厂为了解一批棉花的质量，从中随机抽取了20根棉花纤维进行测量，其长度x（单位：mm）的数据分布如下表所示，则棉花纤维长度的数据在8≤x＜32这个范围的频率为棉花纤维长度x频数0≤x＜818≤x＜_刷题宝

题干

某棉纺厂为了解一批棉花的质量，从中随机抽取了20根棉花纤维进行测量，其长度x（单位：mm）的数据分布如下表所示，则棉花纤维长度的数据在8≤x＜32这个范围的频率为（）

棉花纤维长度x	频数
0≤x＜8	1
8≤x＜16	2
16≤x＜24	8
24≤x＜32	6
32≤x＜40	3

A： 0.8

B： 0.7

C： 0.4

D： 0.2

上一题下一题 0.0难度选择题更新时间:2020-02-13 12:23:28

答案(点此获取答案解析）

A

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B

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