(A) A random sample of 18 Kennewick residents looked at how many miles residents were commuting...

(A) A random sample of 18 Kennewick residents looked at how many miles residents were commuting (two ways) to get to work and back. The survey found that the average number of miles they commute had a mean of 23.2 miles round trip, and a standard deviation of 18.1 miles. a.) Calculate a 95% confidence interval for the true mean commute distances of Kennewick residents.

(B) Interpret your interval from part (a.)

Solutions

Expert Solution

The solution is done showing all steps with calculations and required explanations. For your better understanding, a t table is also attached. Hope you can understand and appreciate the work.

(a)

t table -

(B) We are 95% confident that the interval (14.2,32.2) contains the true population mean.

orchestra answered 1 year ago

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