People were randomly selected and asked how long they study for a statistics exam. A sample of twenty people had a mean time of 8.4 hours and a standard deviation of 1.23 hours. Assume the distribution is normal. What is the point estimate for this sample? (2 pts) Find a 95% confidence interval for the mean number of hours people sleep at night. (6 pts)
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Point estimate: The point estimate for this sample is the mean time of 8.4 hours. Show more…
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