The distribution of the numbers of hours that students at a certain college studied for final exams has a mean of 12 hours and a standard deviation of 3 hours.Which of the following numbers of hours are within 2 standard deviations of the mean of the distribution?Indicate all such numbers
A.2 B.5 C10 D.14 E.16
人气：203 ℃ 时间：2020-03-29 19:59:12
解答
答案选CDE麻烦给下解答思路呗大致意思是学生为学习，学习时间平均为12小时，一个标准区间是3小时。问以下哪些时间处于平均时间加减2个标准区间内这个就是高斯分布的概念题啦，就是看在12-2×3=6和12+2×3=18，看看哪些选项在6到18之间啦
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