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The dean at a university states that the average GPA of stud…

The dean at a university states that the average GPA of students is less than 3.2 You decide to survey 120 students and from this sample you calculate the mean GPA is 3.14 and the standard deviation is 0.35 Test the dean’s claim at the 5% significance level.  a) Find the p-value [pvalue]b) Is there enough evidence to support the dean’s claim, or is there not enough evidence to support the dean’s claim. [decision]

The following table shows data collected for hours spent onl…

The following table shows data collected for hours spent online and test scores for various students.    Hours spent online (x) Test Score (y) 0 96 1 85 2 82 3 74 3 90 5 81 5 83 7 75 10 50 (a) Find the sample correlation coefficient (r) for this dataset [corr] (b) Determine if the correlation is significant, or not significant (use a significance level of 0.05) [sign]  

Three different diet plans are to be tested for mean weight…

Three different diet plans are to be tested for mean weight loss.  Results are shown below (data represents weight loss in pounds for the participants in the study). The claim is that at least one mean is different from the others among the three plans. Using a level of significance of 0.05, test the claim. (a) Determine the p-value [pvalue] (b) Come to a conclusion [concl] Diet Plan #1 Diet Plan #2 Diet Plan #3 4 10 5.5 7.5 5.5 6.5 3.5 12.5 2 12 16 6 6 1.5 7

You decide to order 22 pizzas from Pizza Hut and record the…

You decide to order 22 pizzas from Pizza Hut and record the delivery times. For the sample of 22 pizzas, the average delivery time turns out to be 29 minutes with a sample standard deviation of 2.5 minutes. What is the margin of error, E (round your answer to 3 decimal places) [moe] What is a 90% confidence interval for the true mean delivery time for Pizza Hut (round your answer to 3 decimal places) [conf]