Exercise 2Let X equal the length of life of a 60-watt light bulb marketed by a certain manufacturer.We do not know the distribution of X except that Var(X) = 1158. Let u be the mean of X.Suppose a random sample of n = 25 bulbs is tested until they burn out, yielding a samplemean of x = 1368 hours.(i) Compute an approximate 95% confidence interval for u.(ii) Compute an approximate 95% one-sided confidence interval for that provides alower bound for u, i.e. compute & such thatP(X - ε ≤ μ) ≈ 0.95.

Given information: VX=1158n=25x¯=1368

Answered: Let X equal the length of life of a…

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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Let X equal the length of life of a 60-watt light bulb marketed by a certain manufacturer. We do not know the distribution of X except that Var(X) = 1158. Let u be the mean of X. Suppose a random sample of n = 25 bulbs is tested until they burn out, yielding a sample