In a lab exercise, 25 students will measure the pH value in a water sample. Let X be a stochastic variable that stands for the result of the measurement from a student. X is assumed to be normally distributed with expectation u = 7.0 and standard deviation o = 0.05. a) What is the probability that the result of the measurement from an arbitrary student is between 6.98 and 7.02? b) Let Y be a stochastic variable that represents the average value of the results from these 25 students. What is the probability that the average value is between 6.98 and 7.02? c) Now assume that the expectation u is unknown and the average value of the results from these 25 students is 7.1. Find a 98% confidence interval for the real u.

In a lab exercise, 25 students will measure the pH value in a water sample. Let X be a stochastic variable that stands for the result of the measurement from a student. X is assumed to be normally distributed with expectation u = 7.0 and standard deviation o = 0.05. a) What is the probability that the result of the measurement from an arbitrary student is between 6.98 and 7.02? b) Let Y be a stochastic variable that represents the average value of the results from these 25 students. What is the probability that the average value is between 6.98 and 7.02? c) Now assume that the expectation u is unknown and the average value of the results from these 25 students is 7.1. Find a 98% confidence interval for the real u.

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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