Explore BrainMass

Confidence Interval

(TCO 7) A marketing firm wants to estimate the average amount spent by patients at the hospital pharmacy. For a sample of 100 randomly selected patients, the mean amount spent was $65.30 and the standard deviation $8.15.

(a) Find a 99% confidence interval for the mean amount spent by patients at the pharmacy. Show your calculations and/or explain the process used to obtain the interval.

(b) Interpret this confidence interval and write a sentence that explains it.

Solution Summary

A Complete, Neat and Step-by-step Solution is provided in the attached file.