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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
Lecture Examples
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 