A phone company randomly selects 121 phones from the production line to launch a new model and fin them to have a standard deviation of 110 hours and an average usage time of 2600 hours. Find the 95% confidence interval for the average lifespan of the company's phones. 30 - a) 1580,4-1619.6 O B) 2580,4-2919.6 O C) 2880.4-2619.6 OD) 2580,4-2619.6 O TO) 2880.4-2612.6

A phone company randomly selects 121 phones from the production line to launch a new model and fin them to have a standard deviation of 110 hours and an average usage time of 2600 hours. Find the 95% confidence interval for the average lifespan of the company's phones. 30 - a) 1580,4-1619.6 O B) 2580,4-2919.6 O C) 2880.4-2619.6 OD) 2580,4-2619.6 O TO) 2880.4-2612.6

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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