Cell phones have become an essential part of our everyday lives. We use them for communication, photography, browsing, and banking, among other things. Choosing the right cell phone is important, and is based on several factors, including weight. Suppose the weight of a cell phone is distributed normally with a known population standard deviation of 18 g. A random sample of 15 cell phones was conducted to calculate a sample mean weight of 155.7 g. Construct a 95% confidence interval for the population mean weight, mu. Choose the correct answer below based on constructing this interval (it may be a good idea to write your final interval down, as the next question may relate to this one). Hint: although the sample size is small, you may use the standard normal distribution, as the population standard deviation is known. Hint: we cover this in the video "CI 2020 2" a. the interval is [146.59, 164.81); the critical value used is 1.96 O a) O b) 18 b. the interval is (146.59, 164.81] ; the margin of error is (1.96 * ViS c) c. the interval is (146.59, 164.81]; the margin of error is (1.645 ) 18 d) d. the interval is [137.70, 173.70] ; the margin of error is (1.96 ) O e) e. both a and b are correct

Cell phones have become an essential part of our everyday lives. We use them for communication, photography, browsing, and banking, among other things. Choosing the right cell phone is important, and is based on several factors, including weight. Suppose the weight of a cell phone is distributed normally with a known population standard deviation of 18 g. A random sample of 15 cell phones was conducted to calculate a sample mean weight of 155.7 g. Construct a 95% confidence interval for the population mean weight, mu. Choose the correct answer below based on constructing this interval (it may be a good idea to write your final interval down, as the next question may relate to this one). Hint: although the sample size is small, you may use the standard normal distribution, as the population standard deviation is known. Hint: we cover this in the video "CI 2020 2" a. the interval is [146.59, 164.81); the critical value used is 1.96 O a) O b) 18 b. the interval is (146.59, 164.81] ; the margin of error is (1.96 * ViS c) c. the interval is (146.59, 164.81]; the margin of error is (1.645 ) 18 d) d. the interval is [137.70, 173.70] ; the margin of error is (1.96 ) O e) e. both a and b are correct

ENGR.ECONOMIC ANALYSIS

14th Edition

ISBN:9780190931919

Author:NEWNAN

Publisher:NEWNAN

Chapter1: Making Economics Decisions

Section: Chapter Questions

Problem 1QTC

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