Historically, the earnings of mechanical engineers, graduates of any university, have followed anormal distribution with a standard deviation of $300, have followed a normal distribution witha standard deviation of $300. In a certain study, a random sample of 25 engineers a randomsample of 25 engineers from EPN and an independent sample of 30 engineers from ESPE weretaken. From the results of the sample, it was observed that the average income of the EPNengineers was $1,000 with a standard deviation of $275; and that the ESPE engineers had anaverage income of $1,300 and a standard deviation of $350.a) At a 98% confidence level, is it reasonable to assume that the standard deviations of theearnings of EPN and ESPE engineers are equal? are the earnings of EPN and ESPE engineersequal?b) With a 90% confidence level, is it reasonable to say that the average income of EPNengineers is lower than that of ESPE engineers? EPN engineers is lower than that of ESPEengineers?

Answered: Historically, the earnings of…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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