Posted by Lost37 on Thursday, March 21, 2013 at 12:45am.
A random sample of 60 riders waited in line a mean time of 42 minutes with standard deviation 12 minutes. Find a 90% confidence interval for the populationmean waiting time in line

Statistics  PsyDAG, Thursday, March 21, 2013 at 12:59pm
90% = mean ± 1.645 SEm
SEm = SD/√n