A random experiment was conducted to see if a newly formulated drug produced a different effect on the mean recovery time than that achieved using the standard drug. Following an experiment of 12...

A random experiment was conducted to see if a newly formulated drug produced a different effect on the mean recovery time than that achieved using the standard drug. Following an experiment of 12 patients the average recovery time was 23 days,and a standard deviation of 4 days. Construct a 90% confidence interval for thetrue average recovery time of patients taking the drug.