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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

Problem 1

9.6 t-Test to Compare Two Population Means: Independent Samples (Unequal Variances)

Does marijuana use make you slow?  A random selection of 28 heavy marijuana users spent an average of 38.28 minutes to complete a set of logic puzzles.  Their standard deviation was 4.51 minutes.  A random selection of 29 non users spent an average of 25.4 minutes to complete the same set of logic puzzles.  Their standard deviation was 3.98 minutes. Use a 0.01 significance level to test the claim that the population of heavy marijuana users takes longer on average to complete the set of problems than non users (Do not assume equal variances). 

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