6.2.6 In a survey of introductory statistics students, an in- structor asked her students to report how many Facebook friends they had. Suppose that the intent is to study whether there is an association between number of Facebook friends and a person's sex.

24. The personnel manager of a consumer product company asked a random sample of employees how they felt about the work they were doing. The following table gives a breakdown of their responses by gender. Do the data provide sufficient evidence to conclude that the level of job satisfaction is related to gender? Use a = 0.10 Gender Male Female Very Interesting 70 35 Response Fairly Interesting 41 34 Not Interesting 9 11

Medical researchers followed 6272 Swedish men for 30 years to see if there was any association between the amount of fish in their diet and prostate cancer. (“Fatty Fish Consumption and Risk of Prostate Cancer,” Lancet, June 2001).  A summary of the data is given in the table below.  Fish Consumption No Prostate Cancers Prostate Cancers Never/Seldom 110 14 Small part of diet 2420 201 Moderate part of diet 2769 209 Large part of diet 507 42   A) If a patient is randomly selected, what is the probability that he/she had prostate cancer given that fish was never or seldom a part of the diet?  Round your answer to three decimal places and include the leading zero. B) If a patient is randomly selected, what is the probability that s/he ate fish as a large part of their diet given that they had prostate cancer.  Round your answer to two decimal places and include the leading zero.

3. Some sports psychologists believe that an athlete's motivation is related to how many hours they will devote to training in a 2-week period. To see if this is true, a sports trainer measures the motivation (M) and training hours (TH) of a random sample of 8 Olympic-class athletes and obtains the following data: M TH 57 40 74 46 42 38 48 36 75 54 62 42 665 76 550 69 25 a) Is there a significant correlation between M and TH in this sample (a≤.05)? (8 points) b) If another athlete obtained an M score of 70, what would his or her predicted TH score be and what are the 90% bounds to the error of this prediction? (10 points)