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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.

A service provider wants to study the time for handling a customer complaint (in minutes). For a random sample of 16 customers, the mean time is 26.2 min and the standard deviation is 4.6 min. Suppose

State if each of the below statement about simple linear regression and correlation is either true or false.  

What sample size is needed to estimate the proportion of people who own a tablet with 90% confidence and with the margin of error no larger than 0.03?

Company officials were concerned about the length of time a particular drug product retained its potency. A random sample of 10 bottles of the product was drawn from the production line and analyzed for potency (fresh). A second sample of 10 bottles was obtained and stored in a regulated environment for a period of 1 year (stored). They test  H0: the true mean potency for fresh bottles and for bottles stored for 1 year are the same H1: the true mean potency for fresh bottles and for bottles stored for 1 year are different Fill in the blanks by selecting from the dropdown menu. If the test determines that the true mean potency for fresh and the true mean potency for stored bottles are the same when they are actually different, then this is a [fill1] error. If the test determines that the true mean potency for fresh and the true mean potency for stored bottles are different when they are actually the same, then this is a [fill2] error. The [fill3] of the test is the probability that the test determines that the true mean potency for fresh and the true mean potency for stored bottles are different when they are different. The [fill4] of the test is the probability that the test incorrectly determines that the true mean potency for fresh and the true mean potency for stored bottles are different.

For hypothesis tests or confidence intervals for a mean, the theory behind the Central Limit Theorem is to allow the researcher to assume the sample comes from a normal population. Is this statement true or false?