4. According to the credit rating agency Equifax, credit limits on newly issuedcredit cards increased between January 2011 and May 2011. Suppose thatrandom samples of 400 new credit cards issued in January 2011 and 500 newcredit cards issued in May 2011 had average credit limits of $2635 and $2887,respectively. Suppose that the sample standard deviation for these two sampleswere $365 and $412 respectively. Assume that the population standarddeviations for the two populations are unknown and unequal.a) Let μ₁ and μ₂ be the average credit limits on all credit cards issued inJanuary 2011 and in May 2011, respectively. Construct a 98% confidence intervalforМ1 - М2.b) At a 1% significance level, can you conclude that the average credit limit forall new credit cards issued in January 2011 was lower than the correspondingaverage for all credit cards issued in May 2011? Use the Critical Value Approachto make this test.

Answered: Image /qna-images/answer/36734ca1-5ebf-40e5-937b-d3a9a52948e4.jpg

Answered: 4. According to the credit rating…

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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