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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 2

7.2 Large-Sample Confidence Intervals for a Population Mean

A study of children’s weights was conducted in Hong Kong.  A sample of forty children, each 68 inches tall, had a mean weight of 128.9 pounds and a standard deviation of 9.2 pounds.  Create a 96% confidence interval for the true mean weight of children in Hong Kong that are 68 inches tall.  A Chinese researcher claims that the average child in Hong Kong is underweight.  If the cut off weight for being underweight (at 68 inches tall) is 122 pounds, does this interval provide any evidence to contradict the claim that children in Hong Kong are underweight? 

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