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Chapter 7: Q.22 (page 428)

An unknown distribution has a mean 12 and a standard deviation of one. A sample size of 25is taken.

LetX = the object of interest.

What is the mean of ΣX?

Short Answer

Expert verified

The mean ofΣX=300.

Step by step solution

01

Given Information

An unknown distribution has a mean 12 and a standard deviation of one. A sample size of 25 is taken.

02

Explanation

The mean of the unknown distribution μXis 12and the standard deviation (n)is for the sample size of 25objects of interest.

We calculate the mean (μ)of ∑Xas

localid="1648892796831" μ=(n)μx=25×12=300

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