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The average age of residents in a large residential retirement community is 69 years with standard deviation 5.8 years. A simple random sample of 100 residents is to be selected, and the sample mean age

Please note that this question consists of five parts. Show all your work. Just giving the answer without showing work may result in zero for the question.  A researcher claims that more than 24% of the adults in United States are afraid to fly. You want to test this claim. You find that in a random sample of 1075 adults in USA, 292 re afraid to fly. (You may use below provided MINITAB output to answer the following questions) Write the null and alternative hypotheses you would formulate to test the researchers claim. Check any conditions that need to be satisfied in order for you to continue with the above stated hypothesis test. What are the test statistic and the p value for the hypotheses you stated in part 1? Write your final conclusion in the context of this problem (You may use 5% significance level). Based on your conclusion in part 4, is it possible that you made an error? If so what error would that be?   

State whether below statement is either a True or a False statement. If it is false explain why. Please note that you can say something is true if it’s always true. A medical researcher is conducting an experiment to compare the frequencies of occurrences of side effects to treatment by a new drug for two groups of patients, those who had prior treatment and those who had not.  Researchers want to know if there is evidence that patients who have no prior treatment are more likely to have side effect.  The chi-square test for independence is appropriate for this research question.  

Here are copies of Z-table and T-table.  Z table.pdf T_table.pdf  

For each of the below statements, state if it is true or false.  Type II error in the context of a chi-square test for independence is concluding that there is no relationship between two variables when there really is. This is a [fill1] statement.  If the slope of the regression line is positive, then there is a positive linear relationship between the variables. This is a [fill2] statement.  The intercept of the regression line describes the strength of the linear association between X and Y. This is a [fill3] statement.  Correlation between two quantitative random variables X and Y is -0.76. Intercept of the least square regression line of Y on X must be negative. This is a [fill4] statement.

Students in an introductory statistics class participate in a mid-semester survey. They were asked whether having quizzes better prepare them for the midterms. Their opinion of quizzes were coded as “0” if the answer is No, “1” if the answer is somewhat helpful, “2” if the answer is yes. This variable is:  

Please note that this question consists of three parts. Show all your work/explanation. Just giving the answer without adequate work/explanation may result in zero for the question.  Fifty six percent of the undergraduate students in a college lives off-campus, 68% have a car, and 49% live off-campus and have a car. We randomly select an undergraduate student. Are the events “living off-campus” and “have a car” mutually exclusive? Explain your answer.   What is the probability that the student neither lives off-campus nor have a car? What is the probability that he/she has a car, if he/she lives off-campus?

For each of the following, select the correct answer from the dropdown menu.  If A and B are mutually exclusive events then P(A) = P(B) = 0.5 This is a [fill1] statement.  If A and B are independent events, then

Four golfers are asked to play a round of golf each on two consecutive Saturday afternoons. During the first round, one of two club types is to be used.  During the second round, another club type is to be used.  The order in which a golfer uses each club is determined randomly.  Scores are recorded.  To determine if the mean scores differ by type of club, we would use the:

Student Government Association (SGA)  at a college wants to conduct a survey to determine the proportion of students who voted for election of of the SGA President. Since interviewing all the students is not feasible due to practical reasons, they want to determine the sample size (number of students to be interviewed) needed to estimate the true proportion with a margin of error no larger than .1 using a 98% confidence interval. What is the sample size they need to ensure above specifications in their estimation? Choose the appropriate z-multiplier for the calculation from the below provided values.