The manager of a mall conducted a survey among two groups (n1 = 100, n2 = 100) of visitors to the mall on different days. She found that the first group spent an average of 60 minutes in the mall, while the second group spent an average of 90 minutes in the mall.If the manager wishes to see the difference in the average times spent by the two groups in the mall, which of the following sets shows the null hypothesis and alternative hypothesis?Null Hypothesis: There is at least some difference in the average times spent by the two groups in the mall.Alternative Hypothesis: The difference in the average times spent by the two groups in the mall is 30 minutes.Null Hypothesis: There is no difference in the average times spent by the two groups in the mall.Alternative Hypothesis: There is at least some difference in the average times spent by the two groups in the mall.Null Hypothesis: There is at least some difference in the average times spent by the two groups in the mall.Alternative Hypothesis: There is no difference in the average times spent by the two groups in the mall.Null Hypothesis: There is no difference in the average times spent by the two groups in the mall.Alternative Hypothesis: There is a difference in the average times spent by the two groups in the mall, with a standard deviation of 30 minutes.

At one school, the average amount of time that tenth-graders spend watching television each week is 18.4 hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal wants to perform a hypothesis test to determine whether the average amount of time spent watching television per week has decreased. Formulate the null and alternative hypotheses for the study described.Question 17Answera.H0: µ = 18.4 ; H1 µ ≠18.4b.H0: µ < 18.4 ; H1 µ > 18.4c.H0: µ = 18.4 ; H1 µ <18.4d.H0: µ > 18.4 ; H1 µ <18.4

You have recently been appointed as a junior research analyst at a renowned corporation in Johannesburg. You collected data for a pilot study investigating the relationship between hours spent in a mall and the number of purchases made. This pilot study was conducted in a local shopping centre in the CBD. Your employee (senior research analyst) has asked you to provide him with the median of the time spent in a shopping mall and the mean for the number of purchases made.  Table 1 ShopperTime spent in the mallNumber of purchases made16 hours2022 hours1434.5 hours1842 hours1451 hour062 hours1371.5 hours1586 hours1892.5 hours20103 hours14115 hours17_____ is the median of the time spent in the mall and ____ is the mean for the number of purchases made. Group of answer choices6; 172.77; 15.92; 142.5; 14.82

In 2013, the average Girl Scout in New York City sold 96 boxes of cookies. The leader of Troop 5078 in New York City wants to know if the scouts in her troop sold more cookies than the average in New York City. She randomly samples 50 girls in Troop 5078 and records the number of boxes of cookies sold for each girl in the sample.Here are the null and alternative hypotheses for her study: H0: µ = 96, Ha: µ > 96.What does µ represent in these hypotheses? Mean number of boxes of cookies sold for the Girl Scouts in her sample from Troop 5078 Mean number of boxes of cookies sold for the average Girl Scout in New York City Mean number of boxes of cookies sold for the Girl Scouts in Troop 5078

In the past, the mean running time for a certain type of flashlight battery has been 8 hours. The manufacturer has introduced a change in the production method and wants to perform a hypothesis test to determine whether the mean running time has increased as a result. The hypotheses are:H0 : μ < 8 hoursH1 : μ > 8 hoursSuppose that the results of the sampling lead to rejecting of the null hypothesis but, in reality, the mean running time has not increased, how would you classify the conclusion that the researchers made?Question 7Answera.Correct decisionb.Not enough information providedc.Type II errord.Type I error

Amanda is the owner of a small chain of dental offices. She sent out the yearly satisfaction survey to 600 randomly selected patients and received 544 surveys back. When looking through the results, she noticed that the downtown dental office staff had 84% of clients reporting satisfaction with services, while the uptown dental office staff had 76% of clients reporting satisfaction with services.  Which of the following sets shows Amanda's null hypothesis and alternative hypothesis?Null Hypothesis: The proportion of clients satisfied at the downtown office is equal to the proportion of clients satisfied at the uptown office. Alternative Hypothesis: There is a difference in the satisfaction between the uptown and the downtown clients. Null Hypothesis: The proportion of clients satisfied at the downtown office is greater than the proportion of clients satisfied at the uptown office.Alternative Hypothesis: Downtown clients are less satisfied with the dental office staff than uptown clients.Null Hypothesis: The proportion of clients satisfied at the uptown office is 76%.Alternative Hypothesis: There is no difference in the satisfaction between the uptown and the downtown clients.Null Hypothesis: The proportion of clients satisfied at the downtown office is 84%.Alternative Hypothesis: Uptown clients are more satisfied with the dental office staff than downtown clients.