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某棉纺厂为了了解一批棉花的质量,从中随机抽取了100根棉花纤维的长度(棉花纤维的...
某棉纺厂为了了解一批棉花的质量,从中随机抽取了100根棉花纤维的长度(棉花纤维的长度是棉花质量的重要指标),所得数据都在区间[5,40]中,其频率分布直方图如图所示,则其抽样的100根中,有
根在棉花纤维的长度小于20mm.
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的最小值为( )
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