Answer Happy

Medical professionals at a student health center are trying to alert the undergraduate population about the importance of getting sufficient sleep and the role this plays in their academic performance. The health center staff would like to estimate the true average amount of sleep that the undergraduate students are receiving and construct a 90% confidence interval for this estimate Furthermore, in order to be useful, the interval can be no more than 1.8 hours WIDE ( so Margin or Error would be half of that). Table 1 reports the results from a pilot test that measured the amount of sleep obtained in a random sampling of undergraduate students. Use the standard deviation from this pilot study as your estimate for the population standard deviation Table 1: Descriptive statistics for the sleep study Variable mean Std. Dev Hours of sleep 9.5 5.00 Based on the student health department's criteria, the number of students that should be selected is: