1. The local lube shop advertises that it provides a complete lube-oil-filter maintenanceservice in just 20 minutes (or less) on average. You obtain a simple random sample of144 lube-oil-filter service times. The sample average is 26 minutes with sample SD 12minutes. Find a 95% confidence interval for the average lube-oil-filter service time.Based on your interval, do you think that the local lube shop's average service time is 20minutes or less? Or do you think the average time is higher than 20 minutes? Explain.

Suppose µ is the population average lube-oil filter service time..

Answered: 1. The local lube shop advertises that…

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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A psychology graduate student wants to test the claim that there is a significant difference between the IQs of spouses. To test this claim, she measures the IQs of 9 married couples using a standard IQ test. The results of the IQ tests are listed in the following table. Using a 0.10 level of significance, test the claim that there is a significant difference between the IQs assuming that the population distribution of the paired differences is approximately normal. Let the spouse 1 group be Population 1 and let the spouse 2 group be Population 2. Spouse 1 Spouse 2 IQs of Married Couples 124 113 97 123 121 101 128 116 96 126 119 100 Copy Data Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places. 124 111 127 113 107 111
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QUESTION 1 a) Two machines are used to fill glass bottles with a net volume of 13.0ml. The filling processes are assumed to be normally distributed, with common but unknown standard deviations. The quality department suspects that both machines fill to the same net volume, whether or not this volume is 13.0ml. An experiment is performed by taking a random sample from the output of each machine. 13.01 12.98 13.02 13.05 12.99 Machine 1 13.03 13.01 12.96 12.97 13.04 13.04 13.02 13.01 13.05 13.02 Machine 2 13.00 12.96 12.99 13.02 13.03
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