Recall that a bank manager has developed a new system to reduce the time customers spend waiting to be served by tellers duringpeak business hours. The mean walting time during peak business hours under the current system is roughly 9 to 10 minutes. Thebank manager hopes that the new system will have a mean waiting time that is less than six minutes. The mean of the sample of 104bank customer waiting times is 5.48. If we let u denote the mean of all possible bank customer waiting times using the new systemand assume that o equals 2.47:(a) Calculate 95 percent and 99 percent confidence intervals for u. (Round your answers to 3 decimal places.)95 percent confidence intervals for u is99 percent confidence intervals for u is(b) Using the 95 percent confidence interval, can the bank manager be 95 percent confident that u is less than six minutes? Explain.95 percent interval is(c) Using the 99 percent confidence interval, can the bank manager be 99 percent confident that u is less than six minutes? Explain.99 percent interval extends

x = 5.48n = 104σ =2.47 confidence interval : CI = x ± z×σn Two tailed critical value of Z for 95% CI…

Recall that a bank manager has developed a new system to reduce the time customers spend waiting to be served by tellers during peak business hours. The mean walting time during peak business hours under the current system is roughly 9 to 10 minutes. The bank manager hopes that the new system will have a mean waiting time that is less than six minutes. The mean of the sample of 104 bank customer waiting times is 5.48. If we let u denote the mean of all possible bank customer waiting times using the new system and assume that a equals 2.47: (a) Calculate 95 percent and 99 percent confidence intervals for u. (Round your answers to 3 decimal places.) 95 percent confidence intervals for uis 99 percent confidence intervals for u is (b) Using the 95 percent confidence interval, can the bank manager be 95 percent confident that uis less than six minutes? Explain. 05 percent interval is (c) Using the 99 percent confidence interval, can the bank manager be 99 percent confident that u is less than six minutes? Explain. 99 percent interval extends 6.

Recall that a bank manager has developed a new system to reduce the time customers spend waiting to be served by tellers during peak business hours. The mean walting time during peak business hours under the current system is roughly 9 to 10 minutes. The bank manager hopes that the new system will have a mean waiting time that is less than six minutes. The mean of the sample of 104 bank customer waiting times is 5.48. If we let u denote the mean of all possible bank customer waiting times using the new system and assume that a equals 2.47: (a) Calculate 95 percent and 99 percent confidence intervals for u. (Round your answers to 3 decimal places.) 95 percent confidence intervals for uis 99 percent confidence intervals for u is (b) Using the 95 percent confidence interval, can the bank manager be 95 percent confident that uis less than six minutes? Explain. 05 percent interval is (c) Using the 99 percent confidence interval, can the bank manager be 99 percent confident that u is less than six minutes? Explain. 99 percent interval extends 6.

ENGR.ECONOMIC ANALYSIS

14th Edition

ISBN:9780190931919

Author:NEWNAN

Publisher:NEWNAN

Chapter1: Making Economics Decisions

Section: Chapter Questions

Problem 1QTC

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