A maintenance supervisor is comparing the standard version of an instructional booklet with one that has been claimed to be superior. An experiment is conducted in which 26 technicians are divided into two groups, provided with one of the booklets, then given a test a week later. For the 13 using the standard version, the average exam score was 72.0, with a standard deviation of 9.3. For the other 13 using the new version, the average score was 80.2, with the standard deviation of 10.1. Assume normal populations with equal standard deviations, and using the 5% level of significance, does the standard version booklet appear to be better than the new version?

The calculation of the coefficient of determination r² depends on the number of independent variables. An adjusted value of r² based on the number of degrees of freedom is calculated using the formula shown below, where n is the number of data pairs and k is the number of independent variables. 2 adj =1- (1-2) (n-1) n-k-1 Data were found on eight pre-owned sedans of a certain make. Suppose a multiple regression on these data has 6 independent variables. The coefficient of determination is found to be 0.901 based on a sample of 18 paired 2 adj, observations. After calculating r determine the percentage of the variation in y that can be explained by the relationships between variables according to r2d. Compare this result with the one obtained using r². adj

According to the Vivino website, suppose the mean price for a bottle of red wine that scores 4.0 or higher on the Vivino Rating System is $32.48. A New England-based lifestyle magazine wants to determine if red wines of the same quality are less expensive in Providence, and it has collected prices for 64 randomly selected red wines of similar quality from wine stores throughout Providence. The mean and standard deviation for this sample are $30.15 and $12, respectively. (a) Develop appropriate hypotheses for a test to determine whether the sample data support the conclusion that the mean price in Providence for a bottle of red wine that scores 4.0 or higher on the Vivino Rating System is less than the population mean of $32.48. (Enter != for # as needed.) Ho: H: (b) Using the sample from the 64 bottles, what is the test statistic? (Round your answer to three decimal places.) Using the sample from the 64 bottles, what is the p-value? (Round your answer to four decimal places.) p-value =…

Miranda and Karla began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Miranda took a test in Social Studies and earned a 71.4, and Karla took a test in Art History and earned a 60.9. Use the fact that all the students' test grades in the Social Studies class had a mean of 75.3 and a standard deviation of 10.7, and all the students' test grades in Art History had a mean of 66.4 and a standard deviation of 10.3 to answer the following questions.a) Calculate the z-score for Miranda's test grade.z=b) Calculate the z-score for Karla's test grade.z=c) Which person did relatively better? Miranda Karla They did equally well.