A random sample of 12 graduates of a certain secretarial school typed an average of 79 words per minute with a sample standard deviation of 8 words per minute. Assuming a normal distribution for the number of words typed per minute, find a 95% confidence interval for the average number of words typed by all craduates of this school. D Answer is not given in the choices. D (73.92, 84.08) D (61.59, 64.20) O (28.42, 46.57) O (32.48, 43.22)

A random sample of 12 graduates of a certain secretarial school typed an average of 79 words per minute with a sample standard deviation of 8 words per minute. Assuming a normal distribution for the number of words typed per minute, find a 95% confidence interval for the average number of words typed by all craduates of this school. D Answer is not given in the choices. D (73.92, 84.08) D (61.59, 64.20) O (28.42, 46.57) O (32.48, 43.22)

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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