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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

I'm working on the homework in section 2.2, question 16. The first part of the question asks for the summation of the set (7,9,2,-1, and 3) with x(i)-4, and the second part of the question asking for (x(i)-4). I keep getting the answer of 0 for the first part of the question, and the homework says that 0 is the answer for the second part of the question, but I'm not understanding the differences between the two parts of the question, or how to solve them.

Posted to **STATS 1** on Monday, January 20, 2014 Replies: 1

01/20/2014

8:13 PM EST

Hi Christina,

The difference has to do with the parenthesis which changes the order that you perform the operations. Remember that when evaluating expressions, you have to follow the order of operations: Parenthesis, Exponents, Mult/Div, and Add/Sub. Always perform the higher orders first. I have created a video below to explain these two problems.

Hope the video clears it up for you,

Professor McGuckian