3 PM Tue Dec 13 ... 48% webassign.net 11. [-/3 Points] DETAILS MY NOTES ASK YOUR TEACHER 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 98% confidence interval for this estimate. Furthermore, in order to be useful, the interval can be no more than 2.4 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 5 9.50 Based on the student health department's criteria, the number of students that should be selected is: 12. [-/4 Points] DETAILS MY NOTES ASK YOUR TEACHER The First Chicago Bank is reviewing its service charges and interest-paying policies on checking accounts. The daily balance of a checking account is defined to be the balance in the checking account at 2:00pm. The bank has found that for all personal checking accounts the mean of all the daily balances is $ 700 and the standard deviation is $150. In addition, the distribution of personal checking account daily balances can be approximated very well with a normal model. Question 1. What PERCENTAGE of the bank's customers carry daily balances between $700 and $1,000? % (Use 2 decimal places in your answer. Note that the answer is requested as a PERCENT, that is, a value between 0 and 100) Example, if you got 0.1234, you should enter it as 12.34 Question 2. The bank is considering paying interest to customers carrying daily checking account balances in excess of a certain amount. If the bank does not want to pay interest to more than 5% of its checking account customers, what is the minimum daily balance on which it should be willing to pay interest? (Round your answer to the nearest dollar amount) dollars