A student wants to compare textbook prices for two online bookstores She takes a random sample of ve textbook titles from a list provided by her college bookstore, and then she determines the prices of those textbooks at each of the two websites. The prices of the five textbooks selected are listed below in the same order for each online bookstore. A.com: $115, $43, $99, $80, $119 B.com: $110, $40, $99, $69, $109 (a) Are these independent or dependent samples? 0 Dependent. Different textbooks are being compared. 0 Dependent. The same textbooks are being compared. 0 Independent. The same textbooks are being compared. 0 Independent. Different textbooks are being compared. (b) To construct a confidence interval, conditions for the data must be checked. Which variable should be checked? 0 the difference between the textbook price from A.com and the textbook price from B.com for each textbook. 0 the prices of textbooks from B.com O the difference between the average textbook price for A.com and the average textbook price for B.com O the prices of textbooks from A.com (c) Find a 98% confidence interval for the mean difference in textbook prices at the two online bookstores. (Use d = A.com - B.com.) HINT: Use StatCrunch. Enter the two columns of numbers, Stat > t stat > choose the appropriate test and fill in what's needed ( , ) (Use 3 decimal places) (d) Suppose conditions are met. Using a = 0.02, is there evidence to indicate that the mean price of textbooks for A.com differs from the mean price of textbooks for B.com? 0 Because the interval does not contain zero, it is not plausible that the mean difference between A.com and B.com is 0. There is evidence to indicate that the mean price of textbooks for A.com is different from the mean price of textbooks for B.com . 0 Because the interval contains zero, it is not plausible that the mean difference between A.com and B.com is 0. There is evidence to indicate that the mean price of textbooks for A.com is different from teh mean price of textbooks for B.com. 0 Because the interval does not contain zero, it is plausible that the mean difference between A.com and B.com is 0. There is not enough evidence to indicate that the mean price of textbooks for A.com is different from the mean price of textbooks for B.com. 0 Because the interval contains zero, it is plausible that the mean difference between A.com and B.com is 0. There is not enough evidence to indicate that the mean price of textbooks for A.com differs from the mean price of textbooks for B.com. 8. [/6 Points] I DETAILS 0/2 Submissions Used MY NOTES I I PRACTICE ANOTHER A new disease has annihilating amphibian populations at unprecedented levels. Researchers has been trying to develop some treatment that can counteract the disease and save some of the amphibian populations. To test which of two potential solutions is more effective, they take a sample of frogs and randomly divide them into two groups. After being treated, 258 of the 400 frogs in group 1 ended up surviving exposure to the pathogen; 300 of the 482 frogs in the second group survived. For the following questions, calculate your difference in the order: group 1 - group 2. The standard error of the difference was 0.033. (a) What are the hypotheses they should test to see if the treatments given to the two groups have different effectiveness? Ho: vs. Ha: (b) Calculate the test statistic: :] (c) Find the p-value: :] (d) What could we conclude from the test? 0 The treatment given to group 1 was not more effective. 0 The treatment given to group 1 was more effective. 0 The treatment given to group 2 was not more effective. 0 Neither treatment was significantly more effective than the other. 0 The treatment given to group 2 was more effective. You play a game of dice at the state fair, but suspect the dice may have been rigged. You observe the game owner rolling the dice 96 times and note the following results: Face "1.. "2.. "3.. "4.. "5.. "6" Observed count 14 23 11 21 20 7 (a) Which hypotheses should be used to test if the dice are fair: Identify HO: O Ho: p1 = p2 = p3 = p4 = p5 p6 1/6, implying the dice are fair. 0 Ho: p1 = p2 = p3 = p4 = p5 p6 1/6, implying the dice are unfair. O Ho: p1 = p2 = p3 = p4 = p5 p6 = 0, implying the dice are fair. 0 Ho: p1 = p2 = p3 = p4 = p5 p6 = 0, implying the dice are unfair. Identify Ha: 0 Ha: every p 1/6, implying the dice are fair. 0 Ha: every p 1/6, implying the dice are unfair. 0 Ha: at least one pat 1/6, implying the dice are unfair. 0 Ha: at least one p at 1/6, implying the dice are fair. (b) What is the expected count for each side of the dice? (c) Is the cell count condition met? 0 Yes, because the expected cell count is close to the observed cell count for all cells. 0 No, because some cells have less than 30 observed counts. 0 Yes, because the expected cell count is at least 5 for all cells. 0 No, because some cells have less than 10 observed counts. (d) Calculate the contribution to the test statistic for the dice side with number "6": (Use 4 decimals): :]