24 - A telephone company randomly selects 121 telephones from the production line to launch a new model and finds that they have a standard deviation of 110 hours and an average usage time of 2600 hours. Find the confidence interval of 90% probability of the average lifespan of the phones manufactured by the company.

24 - A telephone company randomly selects 121 telephones from the production line to launch a new model and finds that they have a standard deviation of 110 hours and an average usage time of 2600 hours. Find the confidence interval of 90% probability of the average lifespan of the phones manufactured by the company.

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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