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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
9.2 Z-Test to Compare Two Population Means: Independent Samples
Which batteries last longer? A randomly selected sample of 92 Duralife AA batteries had an average lifespan of 46.2hrs with a standard deviation of 2.67 hrs. A randomly selected sample of 91 Energy AA batteries had an average lifespan of 42.9hrs with a standard deviation of 3.17 hrs. Use a 5% significance level to test the claim that Duralife batteries last longer on average.
STATS1
STATS2
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