It is reported that American adolescents spend an average of μ =4 hours per day using smart phone (σ = 2 hours). Assuming the distribution is normal, a. What is the probability of selecting an individual who uses a smart phone more than 8 hours a day? b. what proportion of American adolescents spend between 2.5 and 5.5 hours per day using smart phones?

It is reported that American adolescents spend an average of μ =4 hours per day using smart phone (σ = 2 hours). Assuming the distribution is normal, a. What is the probability of selecting an individual who uses a smart phone more than 8 hours a day? b. what proportion of American adolescents spend between 2.5 and 5.5 hours per day using smart phones?

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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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.

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It is reported that American adolescents spend an average of μ =4 hours per day using smart phone (σ = 2 hours). Assuming the distribution is normal,

a. What is the probability of selecting an individual who uses a smart phone more than 8 hours a day?

b. what proportion of American adolescents spend between 2.5 and 5.5 hours per day using smart phones?

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