Problem 5Lightbulbs of a certain type are advertised as having an average lifetime of 750 hours. The priceof these bulbs is very favourable, so a potential customer has decided to go ahead with a purchasearrangement unless it can be conclusively demonstrated that the trne average lifetime is smallerthan what is advertised. A random sample of 43 bulbs was selected and it gives an average of 738.44hours, with standard deviation 38.20 hours.a) Does the data provide evidence for concluding that the true average lifetime of the bulbs is lessthan 750 hours? Carry out a test of hypotheses using a a02 confidence level.b) Calculate a upper confidence bound using a confidence level of 98% for the average lifetime forsuch certain type of bulbs.c) Is the result achieved in part b) supporting the one obtained in part a)? Explain,

a) Hypothesized Population Mean (µ) = 750 Hr The provided sample mean is = 738.44 Hr Sample…

Answered: Problem 5 Lightbulbs of a certain type…

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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