The populaion mean annual salary of service desk managers is $48,000 with a standard deviation of $1,800. A sample of 36 service desk managers is randomly selected. What is the probability the mean annual salary of the sample is less then $47,550?

Z = (score-mean)/SEm

Score = sample mean

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to the Z score.