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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
9.1 Z-Interval to Compare Two Population Means: Independent Samples
A researcher theorized that average heights of boys and girls of the same age prior to undergoing puberty should be the same. Fifty-eight randomly selected boys of age 8 had an average height of 123.5 cm with a variance of 98cm. Fifty-five randomly selected girls had an average height of 126.1 cm with a variance of 119cm. Find the 99% confidence interval for the true mean difference between boys and girls heights at age 8. Is there a significant difference?
STATS1
STATS2
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