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In: Statistics and Probability

Moonbucks coffee shop believes that on average, 20 cars go through the drive-thru every 30 minutes...

  1. Moonbucks coffee shop believes that on average, 20 cars go through the drive-thru every 30 minutes and the standard deviations is known to be 8 cars. A random sample of 25 half-hour periods is taken and the sample mean is found to be 24. Test the null hypothesis that the mean is 20. Use an alpha of .05. Make it a two-tail test and assume the distribution is normally distributed.

b . Develop a 95 confidence interval and interpret it in two ways.

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