A computer manufacturer estimates that its line of minicomputers has, on average, 7.7 days of downtime per year. To test this claim, ananalyst contacts seven companies that own one of these computers and is allowed to access company computer records. It isdetermined that, for the sample, the average number of downtime days is 4.9, with a sample standard deviation of 1.3 days. Assumingthat number of downtime days is normally distributed, test to determine whether these minicomputers actually average 7.7 days ofdowntime in the entire population. Let a = .01.Appendix A Statistical Tables(Round your answer to 2 decimal places, e.g. 15.25.)The value of the test statistic isand we

Given that Sample size n = 7 Sample mean = 4.9 Sample SD = 1.3 Level of significance = 0.01

Answered: A computer manufacturer estimates 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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The manager of a computer retails store is concerned that his suppliers have been giving him laptop computers with lower than average quality. His research shows that replacement times for the model laptop of concern are normally distributed with a mean of 3.3 years and a standard deviation of 0.6 years. He then randomly selects records on 31 laptops sold in the past and finds that the mean replacement time is 3.1 years.Assuming that the laptop replacement times have a mean of 3.3 years and a standard deviation of 0.6 years, find the probability that 31 randomly selected laptops will have a mean replacement time of 3.1 years or less.P(M < 3.1 years) = Enter your answer as a number accurate to 4 decimal places. NOTE: Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted.Based on the result above, does it appear that the computer store has been given laptops of lower than average quality? No. The probability of obtaining this data is high enough…
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