6. A researcher is looking at the study habits of college students. A random sample of 42 freshmen reported a mean study time of 15.0 hours per week. A random sample of 39 seniors reported a mean study time of 23.0 hours per week. Construct a 95% confidence interval to estimate the true difference between the amounts of time per week that freshmen and seniors spend studying. Assume that study times for freshmen have a standard deviation of 4.7 hours per week, while the study times of seniors have a population standard deviation of 5.2 hours week.
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The point estimate of the difference between the mean study times of freshmen and seniors is: 23 - 15 = 8 hours per week Show more…
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