An automobile repair shop has determined that the average servic etime on an automobile is 2 hours with a standard deviation of 32 minutes. a random sample of 64 out of 400 services is selected. what is the probability that this sample will have a mean service time greater than 114 minutes

Respuesta :

avg. service time = 2hrs +/- 32 mins = 180 mins +/- 32 mins = 148 mins or 212 mins.

Random sample = 64/400 = 16 % of the total population.

Seriously I dont know the answer to the problem, but it is an interesting question, and it forces me to study probability more.