In a survey to estimate the mean time spent by office workers per day checking for and sending out e-mails, a random sample of 30 office workers were selected. The sample mean time spent checking for and sending out e-mails by the 30 office workers per day was reported to be 2 hours. Assumed that the population standard deviation of time spent checking for and sending out e-mails per day was 20 minutes i. Estimate the 95% confidence interval for the true mean time spent checking for and sending out e-mails per day by all the office workers. ii. What must be the minimum sample size so that the sampling eror of part (i) do not exceed 5 minutes at the 95°% confidence level?

In a survey to estimate the mean time spent by office workers per day checking for and sending out e-mails, a random sample of 30 office workers were selected. The sample mean time spent checking for and sending out e-mails by the 30 office workers per day was reported to be 2 hours. Assumed that the population standard deviation of time spent checking for and sending out e-mails per day was 20 minutes i. Estimate the 95% confidence interval for the true mean time spent checking for and sending out e-mails per day by all the office workers. ii. What must be the minimum sample size so that the sampling eror of part (i) do not exceed 5 minutes at the 95°% confidence level?

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Description: In a survey to estimate the mean time spent by office workers per day checking forand sending out e-mails, a random sample of 30 office workers were selected. Thesample mean time spent checking for and sending out e-mails by the 30 officeworkers per

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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