15. The owner of a large car dealership believes that the finandal crisis decreased the number ofcustomers visitng her dealershlp. The dealership has historically had 800 customers per day.The owner takes a sample of 100 days and finds the average number of customers visitingthe dealership per day was 750. Assume that the population standard deviation is350. At the5% significance level, the decision is toA. reject Ho; we can conclude that the mean number of customers visiting the dealershipis significantly less than 800B. reject Ho; we cannot conclude that the mean number of customers visiting thedealership is significantly less than 800C. do not reject Ho; we can conclude that the mean number of customers visiting thedealership is significantly less than 800D. do not reject Ho; we cannot conclude that the mean number of customers visiting thedealership is significantly less than 80016. Calcium is an essential nutrient for strong bones and for controlling blood pressure and heartbeat. Because most of the body's calcium is stored in bones and teeth, the body withdrawsthe calcium it needs from the bones. Over time, if more calcium is taken out of the bones thanis put in, the result may be thin, weak bones. This is especially important for women who areoften recommended a calcium supplement. A consumer group activist assumes that calciumcontent in two popular supplements are normally distributed with the same (assumed equal)unknown population variance, and uses the following information obtained under independentsampling:Supplement 1Supplement 2I= 1,000r1,016 mgS= 23 mg$y=24 mgP=12Let u and p, denote the corresponding population means, Construct a 95% confidenceinterval for the difference H .A. [-30.9386, 1.0614]B. [-31,5886, -0,4114]C. [-33.8007, 1,8007]D. [-34.8012, 2.8012]

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15. The owner of a large car dealership believes that the financial crisis decreased the number of customers visiting her dealershlp. The dealershlp has historically had 800 customers per day. The owner takes a sample of 100 days and finds the average number of customers visiting the dealership per day was 750. Assume that the population standard deviation is350. At the 5% significance level, the decision is to A. reject Ho; we can conclude that the mean number of customers visiting the dealership is significantly less than 800 B. reject Ho; we cannot conclude that the mean number of customers visiting the dealership is significantly less than 800 C. do not reject Ho; we can conclude that the mean number of customers visiting the dealership is significantly less than 800 D. do not reject Ho; we cannot conclude that the mean number of customers visiting the dealership is significantly less than 800

15. The owner of a large car dealership believes that the financial crisis decreased the number of customers visiting her dealershlp. The dealershlp has historically had 800 customers per day. The owner takes a sample of 100 days and finds the average number of customers visiting the dealership per day was 750. Assume that the population standard deviation is350. At the 5% significance level, the decision is to A. reject Ho; we can conclude that the mean number of customers visiting the dealership is significantly less than 800 B. reject Ho; we cannot conclude that the mean number of customers visiting the dealership is significantly less than 800 C. do not reject Ho; we can conclude that the mean number of customers visiting the dealership is significantly less than 800 D. do not reject Ho; we cannot conclude that the mean number of customers visiting the dealership is significantly less than 800

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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