3) A mathematics teacher recently graded a chapter test for students in his abstract algebra course. In a review of his grading, he found the mean score out of 100 points was a x = 73, with a margin of error of 9. Construct a confidence interval for the mean score (out of 100 points) on the chapter test. Confidence Interval: (64,82)

A research scientist wishes to test the claim that the mean number of children per classroom in California elementary school is less than 35. She selects a simple random sample of 29 California elementary school classrooms. She know nothing about the distribution of children in classrooms. Can she use the data to test her claim?

The U.S. Department of Transportation, National Highway Traffic Safety Administration, reported that 77% of all fatally injured automobile drivers were intoxicated. A random sample of 52 records of automobile driver fatalities in a certain county showed that 35 involved an intoxicated driver. Do these data indicate that the population proportion of driver fatalities related to alcohol is less than 77% in Kit Carson County? Use ? = 0.10. What is the value of the sample test statistic? (Round your answer to two decimal places.)=__   (c)Find the P-value of the test statistic. (Round your answer to four decimal places.)=__

The 95% confidence interval of the variance of a population is computed as (12.367,21.761). Interpret this confidence interval.

A researcher wanted to find the best viewing distance for watching a TV screen. He recruited the following number of participants and asked them to evaluate their satisfaction of the viewing distance. Then, he conducted an ANOVA to see if there is any significant mean differences. Here are the number of participants by each group: Group 1 (4 feet) - 5 people Group 2 (7 feet) - 5 people Group 3 (10 feet) - 6 people Group 4 (13 feet) - 5 people Group 5 (16 feet) - 4 people Given the numbers as presented above, what is the degrees of freedom for within groups for this analysis? a. 4 b. 20 O c. 21 d. 25

A psychology student conducted a study on using a chief executive​ officer's facial structure to predict a​ firm's financial performance. The facial​ width-to-height ratio​ (WHR) for each in a sample of 55 CEOs at publicly traded firms was determined. The sample resulted in x=1.74 and s=2.02. The student wants to predict the financial performance of a firm based on the value of the true mean facial WHR of CEOs. The student wants to use the value of μ=2.3. Do you recommend he use this​ value? Conduct a test of hypothesis for μ to help you answer the question. Specify all the elements of the​ test, including H0​, Ha​, test​ statistic, p-value, and your conclusion. Test at α=0.10.   Find the​ p-value.   ​p-value=enter your response here ​(