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Chapter 8: Q 68. (page 542)

Travel time to work A study of commuting times reports the travel times to work of a random sample of 20employed adults in New York State. The mean is x¯=31.25minutes and the standard deviation is sX=21.88

minutes. What is the standard error of the mean? Interpret this value in context.

Short Answer

Expert verified

Standard error of mean value is4.892.

Step by step solution

01

Given Information

It is given that (x¯)=31.25

sx=21.88

n=20

02

Concept Used

Formula to be used is
SEx¯=sxn

03

Calculation

We can calculate standard error of mean as

SEx¯=sxn

=21.8820

=4.892

Hence, standard error of mean is4.892

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