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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 146 In 1995, the American Cancer Society randomly sampled 1500 adults of which 555 smoked. In 2005, they surveyed 1750 adults and found that 578 of them smoked. Form a 90% confidence interval for the difference between the proportion of smokers in 1995 and 2005. Has the proportion decreased over the ten year period?