posted by Anonymous .
the average length of time for students to register for fall classes at a certain college has been 50 minutes. a new registration procedure using modern computing machine is being tried. if a random sample of 12 students had an average registration time of 42 minutes with a standard deviation of 11.90 minutes under the new system, test the hypothesis that the population mean is now less than 50 using 0.01 level of significance. Assume the population of times to be normal
Use the z-score formula to get your value then look it up : )