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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

Ask the Professor Forum

Hi Professor,
I got a similar answer for #20 on HW 7.2 but it wasn't as exact.
Can you help me find out what I did wrong?

My final answer is: [821,420.1 , 4,224,149.9]

My margin of error concluded to be: 1,701,364.938
My z alpha/2 is: 2.33

Posted to STATS 1 on Monday, November 18, 2013   Replies: 2

Professor Mcguckian
7:12 PM EST

Hi Christina,

Your answer is a little off because of the critical z value that you used. It seems you did not use the t-table to find the critical value. I actually created a video for this problem to answer another student's question.  Click the 'Ask the Professor' link and find the question category for 'Confidence Interval for Mean'.

Watch the video for more detail,

Professor McGuckian

10:46 PM EST
Okay thank you

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