A population has a variance of 867. We take a random sample of size 47 from this population. Let Xbar be the sample mean and let Xtot be the sample sum of our sample. These are random variables. a) What is the standard deviation of this population? b) What is the variance of Xbar? (to three decimal places) c) What is the standard deviation of Xbar? (to three decimal places)

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.