To estimate the average gestation time (time being carried in the womb between conception and birth) for humans, a researcher collected data from a sample of 20 babies and found that average gestation time in the sample is 245 days with a sample deviation of 10 days. Assume that the distribution of gestation time is Normal. What is a 96% confidence interval for μ? A. 245 ± 4.58 B. 245 ± 4.93 C. 245 ± 4.71 D. 245 ± 3.91
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We are given the sample mean (x̄) = 245 days, sample standard deviation (s) = 10 days, and sample size (n) = 20. Show more…
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