2021年3月18日,位于孝感市孝南区长兴工业园内的湖北福益康医疗科技有限公司正式落地投产,这是孝感市第一家获批的具有省级医疗器械生产许可证资质的企业,也是我市首家“一次性使用医用口罩、医用外科口罩”生产企业。在暑期新冠肺炎疫情反弹期间,该公司加班加点生产口罩、防护服,消毒水等防疫物品,保障抗疫一线医疗物资供应,在社会上赢得一片赞誉.在加大生产的同时,该公司狠抓质量管理,不定时抽查口罩质量,该企业质检人员从所生产的口罩中随机抽取了100个,将其质量指标值分成以下六组:
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo+stretchy%3D%22false%22%3E%5B%3C%2Fmo%3E%3Cmn%3E40%3C%2Fmn%3E%3Cmi%3E++%EF%BC%8C+%3C%2Fmi%3E%3Cmn%3E50%3C%2Fmn%3E%3Cmo+stretchy%3D%22false%22%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
,
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo+stretchy%3D%22false%22%3E%5B%3C%2Fmo%3E%3Cmn%3E50%3C%2Fmn%3E%3Cmi%3E++%EF%BC%8C+%3C%2Fmi%3E%3Cmn%3E60%3C%2Fmn%3E%3Cmo+stretchy%3D%22false%22%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
,
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo+stretchy%3D%22false%22%3E%5B%3C%2Fmo%3E%3Cmn%3E60%3C%2Fmn%3E%3Cmi%3E++%EF%BC%8C+%3C%2Fmi%3E%3Cmn%3E70%3C%2Fmn%3E%3Cmo+stretchy%3D%22false%22%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
,…,
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmo+stretchy%3D%22false%22%3E%5B%3C%2Fmo%3E%3Cmn%3E90%3C%2Fmn%3E%3Cmi%3E++%EF%BC%8C+%3C%2Fmi%3E%3Cmn%3E100%3C%2Fmn%3E%3Cmo+stretchy%3D%22false%22%3E%5D%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
,得到如下频率分布直方图.