A company has been studying the performance of their sales department. The measure of performance used is: average monthly sales amount in dollars. For the past 12 months, the average monthly sales amount has been $4,532 with a standard deviation of $386. Calculate the percentage of months that the average monthly sales amount exceeds $5,800.

Question

A company has been studying the performance of their sales department.  The measure of performance used is: average monthly sales amount in dollars.  For the past 12 months, the average monthly sales amount has been $4,532 with a standard deviation of $386.  Calculate the percentage of months that the average monthly sales amount exceeds $5,800.

PsyDAG · Answer

Z = (score-mean)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability of the Z score. Multiply by 100.