To monitor advanced chemical processes, chemical engineers will consider key process indicators, which may be just production but more often depend on various quantities. Before attempting to improve a process, n = 9 measurements are made on a key performance indicator
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What can the engineer say with 95% confidence about the maximum error, if he uses the sample mean to estimate the true average value of the performance indicator?
With reference to the previous exercise, assume that the key performance indicator has a normal distribution and a 95% confidence interval for the value of the indicator.