1. A chain retailer has target service levels that each location is expected to deliver. The target
established for customer wait times at checkout is 210 seconds or less. The retailer opened a new
location, called Store #140. An analyst was tasked with testing wait times at the new store. Any store
found in violation of the 210-seconds-or-less standard must take action to reduce waiting times.
The analyst took a random sample of 34 customers at Store #140 and measured the time they had to
wait to check out. In the sample of customers, the
experience with check out times at this retailer, the analyst assumed a population standard deviation of
86 seconds.
Perform and interpret a hypothesis test to determine whether the population mean waiting time at the
Store #140 is longer than 210 seconds at the ?? = 0.05 significance level. Is there evidence here that
Store #140 needs to take action to reduce waiting times?
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