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Is it truuuuue?

A small college town builds a new public parking garage in the downtown area. The town leadership plans to cover the structural cost via parking fees. The town consultant who advises the town leadership predicted $140 average revenue per weekday. The leadership wants to test if the consultant’s prediction underestimates the average revenue per weekday. For a random sample of 50 weekdays, daily fees collected resulted in an average of $125 and a standard deviation $15. The appropriate null and alternative hypotheses for this test are 

80 randomly selected PSU students were asked if they participated in at least one sport this summer, and 34 of them answered yes. A 90% confidence interval for PSU students who did not participate in at least one sport this summer is: 

Identify whether it is more appropriate to make inference on population mean or population proportion, if you study 

A company director wants to study the relationship between the company’s sales and the population size by zip code. Her assistant regressed the population size on the sales (i.e. sales as the explanatory variable and population size as the response) and obtained 42% as the coefficient of determination R2 for the model. But the director is interested in knowing the amount of variation in sales explained by the population size, i.e. the coefficient of determination for the regression line with population size as the explanatory variable and sales as the response. 

An article reports that the 95% confidence interval for the true proportion of adults in United States who are afraid to fly is (0.245, 0.297) based on a random sample of size 250. What is the point estimate of the true proportion of adults in United States who are afraid to fly? [fill1] What is the correct interpretation of this interval? [fill2]

In a random sample of 12 students, the average exam score was 81 with a standard deviation of 6. Suppose that exam scores are normally distributed. The 99% confidence interval for the true mean test score is 

The following boxplot displays the test scores (from 0 to 200) in a statistics class with 20 students. Use this boxplot to match the value for each of the following 

What is the minimum sample size needed to estimate the mean height with 95% confidence with a margin of error of 2.5 cm, if the standard deviation is believed to be 15 cm?

Please note that this question consists of five parts. You may use MINITAB to find a final answer. However you MUST show all the mathematical work to get to the final answer. Just giving the answer without adequate work/explanation may result in zero for the question.  An article claimed that 30% of adults use alternative medicine, such as herbal medicines, massage, spiritual healing and acupuncture. To test this, 86 randomly selected adults were asked if they had used at least one alternative medicine therapy during the past year, and 31 of them answered yes.   Set up appropriate null and alternative hypothesis to test if the article’s claim is true. Are the conditions to carry out the above test is satisfied? Show your work for checking the conditions rather simple “yes” or “no” answer. Calculate the test statistic (show the work) Calculate the p value for the test. You may use MINITAB to find the numerical value of the p value for the test. However, you MUST clearly write down the probability statement Write the final conclusion in the context of the problem. Use 5% significance level.