indow Help ng.cengage.com MindTa. NDTAP Q. Sea ent Exercise 09.15 Algo (Population Mean: Sigma Known) Question 1 Hint(s) Check My According to the IRS, individuals filing federal income tax returns prior to March 31 received an average refund of $1,075 in 2018. Consider the populatio "last-minute" filers who mail their tax return during the last five days of the income tax period (typically April 10 to April 15). a. A researcher suggests that a reason individuals wait until the last five days is that on average these individuals receive lower refunds than do early filer Develop appropriate hypotheses such that rejection of Ho will support the researcher's contention. Ho: H is greater than or equal to 1,075 O Ha: H is less than 1,075 O b. For a sample of 400 individuals who filed a tax return between April 10 and 15, the sample mean refund was $940. Based on prior experience a population standard deviation of o = $1,600 may be assumed. What is the p-value (to 4 decimals)? 0.0258 X O c. Using o = 0.05, can you conclude that the population mean refund for "last minute" filers is less than the population mean refund for early filers? Yes d. Repeat the preceding hypothesis test using the critical value approach Using a = 0.05, what is the critical value for the test statistic (to 3 decimals)? Enter negative value as negative number 1.648 State the rejection rule: Reject Ho if z is less than or equal to the critical value. Using the critical value approach, can you conclude that the population mean refund for "last minute" filers is less than the population mean refund for early filers Yes 1751 30 ... Macbook Air 00 2 * EA # 89 LO