A market research firm supplies manufacturers with estimates of the retail sales of their products from samples of retail stores. Marketing managers are prone to look at the estimate and ignore sampling error. An SRS of 15 stores this year shows mean sales of 50 units of a small appliance, with a standard deviation of 8.6 units. During the same point in time last year, an SRS of 21 stores had mean sales of 39.938 units, with standard deviation 16.2 units. An increase from 39.938 to 50 is a rise of about 20%. 1. Construct a 95% confidence interval estimate of the difference µ1 – µ2, where µj is the mean of this year's sales and uz is the mean of last year sales. (а) < (41 – H2) < (b) The margin of error is 2. At a 0.05 significance level, is there sufficient evidence to show that sales this year are different from last year? O A. Yes ОВ. No

A market research firm supplies manufacturers with estimates of the retail sales of their products from samples of retail stores. Marketing managers are prone to look at the estimate and ignore sampling error. An SRS of 15 stores this year shows mean sales of 50 units of a small appliance, with a standard deviation of 8.6 units. During the same point in time last year, an SRS of 21 stores had mean sales of 39.938 units, with standard deviation 16.2 units. An increase from 39.938 to 50 is a rise of about 20%. 1. Construct a 95% confidence interval estimate of the difference µ1 – µ2, where µj is the mean of this year's sales and uz is the mean of last year sales. (а) < (41 – H2) < (b) The margin of error is 2. At a 0.05 significance level, is there sufficient evidence to show that sales this year are different from last year? O A. Yes ОВ. No

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Description: A market research firm supplies manufacturers with estimates of the retail sales of their products from samples of retail stores. Marketingmanagers are prone to look at the estimate and ignore sampling error. An SRS of 15 stores this year shows mean

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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