Question 9SEA local auto mechanic wanted to study the average time between oil changes and collected a simplerandom sample of 41 customers. The average time between the oil changes in the sample is 141.61 days.Construct and interpret a 91% confidence interval for the the average number of days between oil changes.Assume that the population standard deviation is 21.4 days.i. Procedure: Select an answerSelect an answerOne mean Z procedureOne variance x² procedureOne proportion Z procedureOne mean T procedureii. Assumptions: (select everything that applies)Sample size is greater than 30The number of positive and negative responses are both greater than 10Simple random samplePopulation standard deviation is unknownNormal populationPopulation standard deviation is knowniii. Unknown parameter: Select an answerSelect an answerσ², population varianceμ, population meanp. population proportion

Given that Sample size n = 41 Sample mean = 141.61 Population SD = 21.4

Answered: A local auto mechanic wanted to study…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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