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Chapter 8: Q. 60 (page 518)

60. 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¯=31.25 minutes, and the standard deviation is sx=21.88minutes. What is the standard error of the mean? Interpret this value in context.

Short Answer

Expert verified

The standard error of the mean is 4.8925.

Step by step solution

01

Given information

The mean is x¯=31.25 minutes, and the standard deviation is sx=21.88 minutes.

02

Explanation

Utilizing the formula E¯=sxn, to determine the standard error of mean.
Where, Mean x¯is 31.25. The Standard deviation sxis 21.88.
And the Sample size nis 20.
E¯=sxn
=21.8820
=4.8925
Therefore, the standard error of the mean is 4.8925.

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