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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

Example 114

Example 114:  Butt-dialing 911 is a growing problem.  In New York City, a 2012 report stated that 40% of calls made to 911 were dialed in error from cell phones.    The report looked at a sample of 743,000 calls handled by NYC’s 911 operators.  Construct a 98% confidence interval estimate of the true proportion of NYC 911 calls that are made in error.  Before this report the mayor of NYC claimed that more than 45% of the calls made to 911 were due to “butt-dialing.” Did this report contradict the mayor’s claim?

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