After collecting data on remote education for over a year, it was found that the daily screren-time of high-school students follow a normal distribution with mean 313 minutes and standard deviation 67 minutes. a. What is the probability that a randomly selected student will have a daily screen-time greater than 384 minutes? Answer in exact fraction, or rounded to at least 4 decimal places. b. What is the probability that a randomly selected student will have a daily screen-time between 163 minutes and 413 minutes? Answer in exact fraction, or rounded to at least 4 decimal places. c. Schools are starting to implement guidelines on healty screen-time practices for their students. As a first step, a school plans to place a limit on students' screen-times in such a way so that at most 74.78% of their students fall within that time limit. What should the time limit be set at? Answer in exact fraction, or rounded to at least 2 decimal places. minutes

After collecting data on remote education for over a year, it was found that the daily screren-time of high-school students follow a normal distribution with mean 313 minutes and standard deviation 67 minutes. a. What is the probability that a randomly selected student will have a daily screen-time greater than 384 minutes? Answer in exact fraction, or rounded to at least 4 decimal places. b. What is the probability that a randomly selected student will have a daily screen-time between 163 minutes and 413 minutes? Answer in exact fraction, or rounded to at least 4 decimal places. c. Schools are starting to implement guidelines on healty screen-time practices for their students. As a first step, a school plans to place a limit on students' screen-times in such a way so that at most 74.78% of their students fall within that time limit. What should the time limit be set at? Answer in exact fraction, or rounded to at least 2 decimal places. minutes

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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