Abe wants to estimate the mean of a population with standard deviation 10. Betty wants to estimate the mean of a population with standard deviation 20. If both of them take the same number ofsamples, then which of the following statements are correct?(A) If both Abe and Betty use confidence intervals of the same width, then Abe's confidence level is smaller than Betty's(B) If both Abe and Betty use confidence intervals of the same width, then Abe's confidence level is larger than Betty's(C) If Abe and Betty construct confidence intervals with the same confidence level, then the width of Abe's interval is smaller than that of Betty's(D) If Abe and Betty construct confidence intervals with the same confidence level, then the width of Abe's interval is larger than that of Betty's(A) and (C)(B) and (D)(B) and (C).(A) and (D)

Here, standard deviation of Abe is 10 and standard deviation of Betty is 20. Both have same number…

Answered: Abe wants to estimate the mean of a…

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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A researcher wants to determine if there is a significant difference in the average math scores of two different teaching methods (Method A and Method B). He collects a sample of 50 students from each teaching method and calculates their scores. The sample mean score for Method A is 85 and the sample mean score for Method B is 80. The sample standard deviation for Method A is 4 and the sample standard deviation for Method B is 3. Conduct an independent samples t-test to determine if there is a significant difference in the average math scores of the two teaching methods at a significance level of 0.01.
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