Enjoy learning Statistics Online! Please be sure to share and subscribe to our YouTube channel.


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 am confused how to find the standard deviation in the problems in 4.1, number 7 i get that the mean is 1.5 but for the formula for standard deviation i am having trouble doing. Because the formula says the square root of NxPx (1-p)= the standard deviation. So what would I put for N? 4 each time? and for P what would I use?

Posted to STATS 1 on Friday, October 18, 2013   Replies: 2

Professor Mcguckian
6:14 PM EST

Hi Tufic,

I know you already answered this question for yourself, but I am going to post the solution below anyway because I had already finished the video by the time you wrote me saying not to worry about it.


Glad you figured it out on your own though,

Professor McGuckian

9:27 PM EST
thank you :) thats what i did

Post a reply / comment below or click here to submit a new question to the forum.