An electrical firm manufactures light bulbs that have a length life with normal distribution, and a standard deviation of o = 10 hours. A sample of size n = 100 is obtained, and its sample mean is calculated to be ī = 320 hours. Find the 95% confidence interval for the average length life µ. Find the upper 95% bound for the average length life u. Find the lower 95% bound for the average length life u. Give vour answer as intervals. Use - 00 and oo if needed.

An electrical firm manufactures light bulbs that have a length life with normal distribution, and a standard deviation of o = 10 hours. A sample of size n = 100 is obtained, and its sample mean is calculated to be ī = 320 hours. Find the 95% confidence interval for the average length life µ. Find the upper 95% bound for the average length life u. Find the lower 95% bound for the average length life u. Give vour answer as intervals. Use - 00 and oo if needed.

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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