The director of a secretarial school believes that its graduates can type more than 75 words per minute. A random sample of 12 graduates has been found to have an average of 77.2 words per minute with a standard deviation of 7.9 words per minute in a typing test. Using the 0.05 level of significance, test then claim of the director. Use one population z-test/t-test. Determine a) null and alternative hypothesis b) level of significance and critical values c) value of the test statistics, decision about null hypothesis and conclusion.

The director of a secretarial school believes that its graduates can type more than 75 words per minute. A random sample of 12 graduates has been found to have an average of 77.2 words per minute with a standard deviation of 7.9 words per minute in a typing test. Using the 0.05 level of significance, test then claim of the director. Use one population z-test/t-test. Determine a) null and alternative hypothesis b) level of significance and critical values c) value of the test statistics, decision about null hypothesis and conclusion.

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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