A study was carried out on the blood pressure of 60-year-old women with glaucoma. In the study, 200 60-year-old women with glaucoma are randomly selected and their mean systolic blood pressure sample is 140 mmHg and the sample standard deviation is 25 mmHg. (a) Calculate a 90% confidence interval for the true mean systolic blood pressure in the population of 60-year-old women with glaucoma. (b) Suppose the study above was based on 100 women instead of 200, but the sample mean (140) and the standard deviation (25) are the same. Recalculate the 90% confidence interval. The gap gets wider or narrower? Why?

A study was carried out on the blood pressure of 60-year-old women with glaucoma. In the study, 200 60-year-old women with glaucoma are randomly selected and their mean systolic blood pressure sample is 140 mmHg and the sample standard deviation is 25 mmHg. (a) Calculate a 90% confidence interval for the true mean systolic blood pressure in the population of 60-year-old women with glaucoma. (b) Suppose the study above was based on 100 women instead of 200, but the sample mean (140) and the standard deviation (25) are the same. Recalculate the 90% confidence interval. The gap gets wider or narrower? Why?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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