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7. Sampling Distributions & Confidence Intervals: Mean
7. Sampling Distributions & Confidence Intervals: Mean / Confidence Intervals for Population Mean / Problem 15
Problem 15

A wellness researcher is studying the average daily screen time of adults. In a previous analysis, a random sample of 1010 adults showed a mean daily screen time of 5.385.38 hours with a standard deviation of 0.430.43 hours. The researcher claims that the population mean daily screen time is 5.25.2 hours. Assuming the population of screen times are normally distributed, determine whether the calculated tt-value falls between 𝑡0.05-𝑡_{0.05} and t0.05t_{0.05} at the 90%90\% confidence level.