ta electrical firm manufactures flashlight that have length of life that is normallydistributed, with a standard deviation of 35 hours. If a random sample of 150 flashlightshas a mean life of 480 hours, construct a 99% confidence interval for the mean of theflashlights produced by the firm.

Consider X denotes the length of life of flashlight. Standard deviation of X is σ=35. Sample size is…

Answered: dn electrical firm manufactures…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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dn electrical firm manufactures flashlight that have length of life that is normally etributed, with a standard deviation of 35 hours. If a random sample of 150 flashlights has a mean life of 480 hours, construct a 99% confidence interval for the mean of the flashlights produced by the firm.