A simple random sample of 10 items resulted in a sample mean of 80. The population standard deviation is ? = 20. a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. ( , ) b. Assume that the same sample mean was obtained from a sample of 90 items. Provide a 95% confidence interval for the population mean. Round your answers to two decimal places. ( , ) c. What is the effect of a larger sample size on the interval estimate? Larger sample provides a - Select your answer - margin of error.
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To compute the 95% confidence interval for the population mean, we need to use the formula: CI = x̄ ± z*(σ/√n) where x̄ is the sample mean, σ is the population standard deviation, n is the sample size, and z is the z-score corresponding to the desired level of Show more…
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