1.	A geologist believes that a new process will extract gold from rock more effectively than the process that was used previously. She takes two random samples of gold-bearing rocks and treats the first sample using the new process and the second sample using the old process. She concludes that the new process is more effective than the old process. Unfortunately, she is mistaken: the new process is equally effective as the old process, not better. What kind of error has she made?
2	A veterinary researcher is test a new vaccine for feline leukemia, a common and fatal disease of cats. He randomly assigns cats to be vaccinated with the new vaccine or with the old vaccine. Based on the results of this study, he concludes that the new vaccine is no better than the old vaccine. Unfortunately, he has made an error. In fact the new vaccine is much better than the old vaccine. What kind of error has he made?
3.	A Mission college administrator claims the population mean for student's commute time is 30 minutes. A sample of 144 Mission College students shows a sample mean commute time= 32 minutes with sample standard deviation s = 12 minutes. Can you show at 90% confidence that the adminstrator's claim is wrong? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you mustshow either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: Could the administrator's claim be true? YES or NO
4.	An economist claims that 40% of Americans older than 65 work part time. A sample of 200 Americans older than 65 showed 100 worked part time. Can you prove, at 95% confidence, that the economist's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the populationproportion p(from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the economist'sclaim be true? YES or NO
5.	A company claims that their population mean development time for a major new product is 3 months. A sample of 25 projects shows sample mean development time= 3.2 months with standard deviation s = 0.5 months. You can assume that the data is normally distributed. Can you prove at 95% confidence that the claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: Could the (population) mean development time be 3 months? YES or NO
6.	A medical textbook claims that the length of human pregnancy has population mean = 281 days. A sample of 20 pregnancies shows a sample meanx= 284.8 days with standard deviation s = 13 days. Assume that the data is normally distributed. Can you show, at 95% confidence, that the textbook's claim is not true? To get full credit, you must show that the problem passes the requirements todo the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the population mean be 281 days? YES or NO
7.	A commercial weight loss program claims that 50% of all their clients lose at least a significant amount of weight and keep it off for a year. A random sample of 50 clients shows that 20 lost a significant amount of weight and kept it off for a year. Can you show, at 95% confidence, that the program's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population proportion p (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the program's claim be true? YES or NO
8	A nutritionist claimed that the mean daily calcium intake for California women was 1000 milligrams. A random sample of 81 California women showed a sample mean= 960 milligrams with sample standard deviation s = 90 milligrams. Can you prove at 95% confidence that the nutritionist's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the nutritionist's claim be true? YES or NO
9	A bus company claims that the (population) mean for a trip between San Jose and Los Angelesis = 5. 5 hours. A sample of 25 trips shows sample mean= 6 hours with sample standard deviation s = 0.5 hours. Assume the data is normally distributed. Can you prove at 95% confidence that the claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the population mean time for the trip really be 5.5 hours? Select YES or NO
10	The superintendant of a city school system claims that 60% of the parents of children in the system are satisfied with the schools. A random sample of 200 parents shows that 105 are satisfied. Can you prove, at 95% confidence, that the superintendant's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population proportion p (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the superintendent's claim be true? YES or NO
11	An industrial engineer claims the mean time to complete a task is 30 minutes. A sample of workers were given the task and the time to complete it was recorded. Sample data is as follows: Sample meanx = 32.36 sample standard deviation s = 6.24 n = 50 Can you prove, at 95% confidence, that the engineer's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your nulland alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population mean (from Ho) is in that interval. Then, state whether you reject the null hypothesis. Finally, answer the following yes/no question: could the engineer's claim be true? YES or NO
12	A "Stop Smoking" program claimed that 40% (0.40) of their clients successfully stopped smoking. A random sample of 300 clients found that 90 succeeded in quitting smoking. Can you prove, at 95% confidence, that the program's claim is not true? To get full credit, you must show that the problem passes the requirements to do the hypothesis test. Then, state your null and alternate hypotheses. Then, you must show either (a) or (b) below (not both). a.Show your test statistic and p-value. b.Or, show your confidence interval and state whether the population proportion p (from Ho) is in that interval. Then, state whetheryou reject the null hypothesis. Finally, answer the following yes/no question: could the program's claim (40% success) be true? YES or NO