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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

9.4 t-Test to Compare Two Population Means: Independent Samples (Equal 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 (assume equal variances).