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-847726-276225SAMPLE TESTSAMPLE TESTName: ___________________Exam 4On each problem, show what you put into your calculator to find the answer (show your work).When finding the interval for a true population mean, when is the t-distribution used instead of the normal distribution?The price for a particular model of digital camera is shown below for ten randomly selected retailers. Find the interval about the sample mean in which the true mean lies, with a 95% confidence level.225240215206211210193250225202A recent survey of eight randomly selected social networking sites has a mean of 13.1 million visitors for the previous month. Find the 95% confidence interval of the population mean if the s = 4.1 million.According to Time magazine, 37% of all Americans believe that places can be haunted. An imaginary random sample of 205 college students were asked if they believe that places could be haunted and 65 responded yes. Estimate the true proportion of college students who believe in the possibility of haunted places with a 99% confidence level.Does the Time percentage lie within this interval? If a recent study of 100 women older than 55 found that 29% of them were widows, how large a sample size must I have if I want to be 95% sure that the true population proportion is within 3% of the sample mean.In an April 30 media release by Public Policy Polling, when 1219 Iowans were asked who they would vote for in the next presidential election if the candidates were Hillary Clinton and Jeb Bush, 43% said Hillary Clinton, 40% said Jeb Bush. The stated margin of error was ±2.8%. Calculate the confidence level for this poll.If a population proportion has not yet been found, what values for p and q should I use to determine the sample size for an upcoming survey? Explain why you chose your numbers. Name the 5 steps of the traditional hypothesis testing of a conjecture concerning the population mean. Explain under what conditions would the null hypothesis, H0., be rejected if it were a two-tailed z-test.Explain how the p-value used in the p-method of deciding on a claim is calculated.The mean salary of federal government employees on the General Schedule is $59,593. The average salary of 30 randomly selected state employees who do similar work is $58,800 with a ? = $1500. At a 99% confidence level, is their sufficient evidence to claim that state employees earn on average less than federal employees? Use the traditional method and show all steps.The average expenditure per student (based on average daily attendance) for a certain school year was $10,337 with ? = $1,560. A survey of 150 randomly selected students the following year had a mean of $10,798. The school administration claims the mean has not changed. At an ? = 0.05 level of significance, is the school administration correct? A motorist claims that a town’s police department issues an average of 60 speeding tickets per day. Listed below is the number of speeding tickets written for 30 randomly selected days Assume the population standard deviation is 13.4. Is there enough evidence to reject the motorist’s claim at a = 0.05. Use the p-value method and explain how you know your answer is correct.724536686971576083266072588748596056646842575758634973754263Explain when the t-test for the mean of a population is used in hypothesis testingDuring a recent year the average cost of making a movie was $54.8 million. The following year, a random sample of 15 action movies had an average production cost of $62.3 million with a sample standard deviation of $9.5 million. At a 10% level of significance, can it be concluded that a claim that action movies cost more than average to produce. Use the traditional method.The U.S. Bureau of Labor and Statistics reported that a person between the ages of 18 and 34 has had an average of 9.2 jobs. To test whether the published average was correct, a researcher selected a random sample of eight workers (ages from 18 to 34) and recorded how many different places each person had worked. The data is listed below. At a = 0.05, is the government’s claim that the average is 9.2 correct? Use any method you wish for your test.81215619132What are the necessary requirements for testing hypotheses by using proportions?About 30 % of all burglaries are through an open or unlocked door or window. If a random sample of 130 burglaries indicated that 45 were via an open or unlocked door or window, at a 0.05 level of significance, can it be concluded that the true portion has changed? ................
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