In past years students in a large school district were absen

In past years, students in a large school district were absent an average of 5,1 days per year. With the emergence of several viruses in recent years, however, the district superintendent believes that the average number of days that all students are absent has increased. To determine whether or not she is correct, the superintendent randomly selects 40 students who were enrolled in the district during 2013-14 and finds that they missed an average of 6.4. with a standard deviation of 4.3 absences per year. A. With 90% confidence, estimate the average number of absences of all students in this district during 2013-14. Please list any formulas that were used arid interpret the results in the context of the problem. B. Determine whether the average number of absences per year for ail students is still 5,1, or is now greater than 5.1 absences per year. Use a = 0.05 as the level of significance. As you will do for all hypothesis tests. list the null and alternative hypotheses, test statistic, and decision rule. Show all relevant calculations and state your conclusion in the context of the problem. C. Determine whether or not the procedures in parts A and B are valid. D. Interpret the p-value from part B in the context of the problem. In other words, finish the following sentence: The p-value from part B is the probability that . The CVG Board of Directors claims that 92% of all flights to CVG International airport arrive ?On time,? A random sample of 220 flights is selected. A. Fully describe the sampling distribution of the proportion, for a random sample of 220 flights B. Assuming that the CVG Board of Directors claim is true (that 92% of all flights to CVG are on-time), determine the probability that 190 ci fewer of the 220 randomly selected flights to CVG arrive on time. C. Given the results of part B. do you doubt (or reject) the claim of the CVG Board? Explain your reasoning.

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