新型冠状病毒疫情已经严重影响了我们正常的学习、工作和生活.某市为了遏制病毒的传播,利用各种宣传工具向市民宣传防治病毒传播的科学知识.某校为了解学生对新型冠状病毒的防护认识,对该校学生开展防疫知识有奖竞赛活动,并从女生和男生中各随机抽取30人,统计答题成绩分别制成如下频数分布表和频率分布直方图.规定:成绩在80分及以上的同学成为“防疫标兵”.
![](http://tikupic.21cnjy.com/2023/04/12/41/29/4129008843f22656b53aabfd4804617c_318x277.png)
名女生成绩频数分布表:
附:![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsup%3E%3Cmrow%3E%3Cmi%3EK%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E2%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsup%3E%3Cmo%3E%3D%3C%2Fmo%3E%3Cmfrac%3E%3Cmrow%3E%3Cmi%3En%3C%2Fmi%3E%3Cmn%3E%28%3C%2Fmn%3E%3Cmi%3Ea%3C%2Fmi%3E%3Cmi%3Ed%3C%2Fmi%3E%3Cmo%3E%E2%88%92%3C%2Fmo%3E%3Cmi%3Eb%3C%2Fmi%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmsup%3E%3Cmrow%3E%3Cmn%3E%29%3C%2Fmn%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E2%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsup%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E%28%3C%2Fmn%3E%3Cmi%3Ea%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Eb%3C%2Fmi%3E%3Cmn%3E%29%3C%2Fmn%3E%3Cmn%3E%28%3C%2Fmn%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ed%3C%2Fmi%3E%3Cmn%3E%29%3C%2Fmn%3E%3Cmn%3E%28%3C%2Fmn%3E%3Cmi%3Ea%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmn%3E%29%3C%2Fmn%3E%3Cmn%3E%28%3C%2Fmn%3E%3Cmi%3Eb%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ed%3C%2Fmi%3E%3Cmn%3E%29%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmfrac%3E%3Cmn%3E++%EF%BC%8C+%3C%2Fmn%3E%3Cmi%3En%3C%2Fmi%3E%3Cmo%3E%3D%3C%2Fmo%3E%3Cmi%3Ea%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Eb%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ed%3C%2Fmi%3E%3C%2Fmath%3E)
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmi%3EP%3C%2Fmi%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmrow%3E%3Cmsup%3E%3Cmrow%3E%3Cmi%3EK%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E2%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsup%3E%3Cmo%3E%E2%89%A5%3C%2Fmo%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3Ek%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E0%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3C%2Fmrow%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
| 0.100 | 0.050 | 0.025 | 0.010 | 0.005 | 0.001 |
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3Ek%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E0%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3C%2Fmath%3E)
| 2.706 | 3.841 | 5.024 | 6.635 | 7.879 | 10.828 |