1.A study is conducted to determine whether Company ABC retains its workers longer than Company XYZ. The study finds that in a sample of 12 workers at Company ABC their average time with thecompany is 4.2 years. A sample of 10 workers at Company XYZ finds that the average time with the company is 3.5 years. It is known from previous records that both companies are normally distributedwith population standard deviation for Company ABC was 1.5 years and Company XYZ was 1.2 years.(a)In order to test the above proposition, state which statistics distribution you will use and justify your choice.(b)Test the above proposition at the 5% level of significance.

For ABC : Sample mean = x1 = 4.2 n1 = 12 Population standard deviation = 1.5 For XYZ : Sample mean…

Answered: A study is conducted to determine…

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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The breaking strengths of cables produced by a certain manufacturer have historically had a mean of 1825 pounds and a standard deviation of 70 pounds. The company believes that, due to an improvement in the manufacturing process, the mean breaking strength, μ, of the cables is now greater than 1825 pounds. To see if this is the case, 17 newly manufactured cables are randomly chosen and tested, and their mean breaking strength is found to be 1844 pounds. Assume that the population is normally distributed. Can we support, at the 0.05 level of significance, the claim that the population mean breaking strength of the newly-manufactured cables is greater than 1825 pounds? Assume that the population standard deviation has not changed. Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.) (a) State the null hypothesis H0…

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