In a study of consumer credits, 25 randomly selected credit holders were surveyed, and the mean amount of credit in the past year was found to be $3300 and the standard deviation of $420. Use significance level α=0.05 to test that the mean is less than $3500.

In a study of consumer credits, 25 randomly selected credit holders were surveyed, and the mean amount of credit in the past year was found to be $3300 and the standard deviation of $420. Use significance level α=0.05 to test that the mean is less than $3500.

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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