The average content of certain harmful substances downstream of the Han River is 0.6 mg/l, and the standard deviation for this is known to be 0.1 mg/l. As a result of the water quality improvement campaign for one year, we would like to find out whether the specific harmful substances have decreased. In order to collect 100 samples and reduce them to 95% confidence level, the average of the sample should be obtained below what value?

The average content of certain harmful substances downstream of the Han River is 0.6 mg/l, and the standard deviation for this is known to be 0.1 mg/l. As a result of the water quality improvement campaign for one year, we would like to find out whether the specific harmful substances have decreased. In order to collect 100 samples and reduce them to 95% confidence level, the average of the sample should be obtained below what value?

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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