A random sample is drawn from a population of known standard deviation o = 22.1.Construct a 95% confidence interval for the population mean if:(a) n = 121, x = 82.4, s = 21.9(b) n = 81, x = 82.4, s = 21.9(c) How many samples would you need to get a 95% confidence interval of width 2?

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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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A random sample is drawn from a population of known standard deviation o = 22.1. Construct a 95% confidence interval for the population mean if: (a) n = 121, x = 82.4, s = 21.9 (b) n = 81, x = 82.4, s = 21.9 How many samples would you need to get a 95% confidence interval of width 2?