# Question: The waiting time data in Exercise 6 66 may not be

The waiting time data in Exercise 6.66 may not be normally distributed. Transform these data using a natural log transformation. Plot the transformed data on a normal probability plot and discuss your findings. Set up individual and moving range control charts using the transformed data. Plot the natural log of the waiting time data on these control charts. Compare your results with those from Exercise 6.66.

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