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题目
COMM111_S2 Quiz 6: Estimation 测验 6：估计
单项选择题
The sample size needed to estimate a population mean to within 2 units with 95% confidence when the population standard deviation equals 8 is:当总体标准差等于 8 时，以 95% 的置信度将总体均值估计在 2 个单位以内所需的样本量为：
选项
A.a. 一个。61
B.b. 62
C.c. 9
D.d. 8
查看解析
标准答案
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思路分析
To determine the sample size required for estimating a population mean within a specified margin of error, we use the formula n = (Z_{alpha/2} * sigma / E)^2.
First, identify the components: the confidence level is 95%, which gives Z_{alpha/2} ≈ 1.96 for a two-sided interval; the population standard dev......Login to view full explanation登录即可查看完整答案
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