10. [-/7 Points] DETAILS BBUNDERSTAT12HS 7.4.023.S. MY NOTES ASK YOUR TEACHER David E. Brown is an...

Transcribed Image Text:

10. [-/7 Points] DETAILS BBUNDERSTAT12HS 7.4.023.S. MY NOTES ASK YOUR TEACHER David E. Brown is an expert in wildlife conservation. In his book The Wolf in the Southwest: The Making of an Endangered Species (University of Arizona Press), he records the following weights of adult grey wolves from two regions in Old Mexico. Chihuahua region: x variable in pounds 86 75 91 70 79 80 68 71 74 64 Durango region: x2 variable in pounds 68 72 79 68 77 89 62 55 68 68 59 63 66 58 54 71 59 67 USE SALT (a) Use a calculator with mean and standard deviation keys to calculate X1, S1, X2, and S2. (Round your answers to four decimal places.) = S1 x2 = S = (b) Let be the mean weight of the population of all grey wolves in the Chihuahua region. Let be the mean weight of the population of all grey wolves in the Durango region. Find an 80% confidence interval for M - M2. (Round your answers to two decimal places.) lower limit upper limit (c) Examine the confidence interval and explain what it means in the context of this problem. Does the interval consist of numbers that are all positive? all negative? of different signs? At the 80% level of confidence, what can you say about the comparison of the average weight of grey wolves in the Chihuahua region with the average weight of grey wolves in the Durango region? Because the interval contains only positive numbers, we can say that the mean weight of grey wolves is greater in the Chihuahua region. Because the interval contains only negative numbers, we can say that the mean weight of grey wolves is greater in the Durango region. Because the interval contains both positive and negative numbers, we can not say that the mean weight of grey wolves is greater in the Chihuahua region. We can not make any conclusions using this confidence interval. 10. [-/7 Points] DETAILS BBUNDERSTAT12HS 7.4.023.S. MY NOTES ASK YOUR TEACHER David E. Brown is an expert in wildlife conservation. In his book The Wolf in the Southwest: The Making of an Endangered Species (University of Arizona Press), he records the following weights of adult grey wolves from two regions in Old Mexico. Chihuahua region: x variable in pounds 86 75 91 70 79 80 68 71 74 64 Durango region: x2 variable in pounds 68 72 79 68 77 89 62 55 68 68 59 63 66 58 54 71 59 67 USE SALT (a) Use a calculator with mean and standard deviation keys to calculate X1, S1, X2, and S2. (Round your answers to four decimal places.) = S1 x2 = S = (b) Let be the mean weight of the population of all grey wolves in the Chihuahua region. Let be the mean weight of the population of all grey wolves in the Durango region. Find an 80% confidence interval for M - M2. (Round your answers to two decimal places.) lower limit upper limit (c) Examine the confidence interval and explain what it means in the context of this problem. Does the interval consist of numbers that are all positive? all negative? of different signs? At the 80% level of confidence, what can you say about the comparison of the average weight of grey wolves in the Chihuahua region with the average weight of grey wolves in the Durango region? Because the interval contains only positive numbers, we can say that the mean weight of grey wolves is greater in the Chihuahua region. Because the interval contains only negative numbers, we can say that the mean weight of grey wolves is greater in the Durango region. Because the interval contains both positive and negative numbers, we can not say that the mean weight of grey wolves is greater in the Chihuahua region. We can not make any conclusions using this confidence interval.