The quality-control manager at a compact fluorescent light bulb (CFL) factory needs to determine whether the mean life of a large shipment of CFLS is equal to 7,535 hours. The population standard deviation is 840 hours. A random sample of 49 light bulbs indicates a sample mean life of 7,355 hours. a. At the 0.05 level of significance, is there evidence that the mean life is different from 7,535 hours? b. Compute the p-value and interpret its meaning c. Construct a 95% confidence interval estimate of the population mean life of the light bulbs. d. Compare the results of (a) and (c). What conclusions do you reach?

The quality-control manager at a compact fluorescent light bulb (CFL) factory needs to determine whether the mean life of a large shipment of CFLS is equal to 7,535 hours. The population standard deviation is 840 hours. A random sample of 49 light bulbs indicates a sample mean life of 7,355 hours. a. At the 0.05 level of significance, is there evidence that the mean life is different from 7,535 hours? b. Compute the p-value and interpret its meaning c. Construct a 95% confidence interval estimate of the population mean life of the light bulbs. d. Compare the results of (a) and (c). What conclusions do you reach?

Name: The quality-control manager at a compact fluorescent light bulb (CFL)
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Description: The quality-control manager at a compact fluorescent light bulb (CFL) factory needs to determine whether the mean life of a large shipment of CFLS is equal to 7,535 hours. The population standard deviation is 840 hours. A random sample of 49 light b

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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