A cell phone company claims that the average time a person spends on their phone is 12.8 hours a week. A sample of unknown size of phone users was selected, and the mean time they spent on their phones was 12.2 hours in a week, with a standard deviation of 2.3 hours. Using a 90% confidence level, how many people would the company have to sample in order for their hypothesis to be true?

A cell phone company claims that the average time a person spends on their phone is 12.8 hours a week. A sample of unknown size of phone users was selected, and the mean time they spent on their phones was 12.2 hours in a week, with a standard deviation of 2.3 hours. Using a 90% confidence level, how many people would the company have to sample in order for their hypothesis to be true?

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Description: Please help me with this question. Thank you A cell phone company claims that the average time a person spends on their phone is12.8 hours a week. A sample of unknowwn size of phone users was selected, and themean time they spent on their phones was

Algebra and Trigonometry (6th Edition)

6th Edition

ISBN:9780134463216

Author:Robert F. Blitzer

Publisher:Robert F. Blitzer

ChapterP: Prerequisites: Fundamental Concepts Of Algebra

Section: Chapter Questions

Problem 1MCCP: In Exercises 1-25, simplify the given expression or perform the indicated operation (and simplify,...

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