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Course Documents

Chapter 1 - Intro

Chapter 2 - Methods for Describing Sets of Data

Chapter 3 - Probability

Chapter 4 - Discrete Random Variables

Chapter 5 - Normal Random Variables

Chapter 6 - Sampling Distributions

Chapter 7 - Confidence Intervals

Chapter 8 - Tests of Hypothesis: One Sample

Chapter 9 - Confidence Intervals and Hypothesis Tests: Two Samples

Sample Exam I: Chapters 1 & 2

Sample Exam II: Chapters 3 & 4

Sample Exam III: Chapters 5 & 6

Sample Exam IV: Chapters 7 & 8

Example 152

Example 152: A cosmetic company wants to produce silver nitrate for use in its cosmetics.  It is interested in knowing the most productive procedure for producing the silver nitrate from dissolved silver.  It is believed that stirring of the mixture of silver and nitric acid during the dissolving process has an effect on the yield of silver nitrate crystals produced.  To determine the optimal number of revolutions while stirring the company has set up an experiment involving 15 identical samples randomly assigned to one of three stirring scenarios.  The yields (in tons) for the three stirring options are shown below.  At the 2.5% level of significance test the claim that the number of revolutions while stirring has an effect on silver nitrate yield.   

Revs

10rpm

20rpm

30rpm

Yields

3.9

3.2

3.5

3.6

3.1

3.3

3.7

3.3

3.2

3.3

3.3

3.4

3.8

3.4

3.4

Totals

18.3

16.3

16.8

 

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