posted by Joe .
Ticket sales for opening night of a movie have a mean of $2100 with a standard deviation of $450. Assume these ticket sales follow a normal distribution. If a movie is selected randomly, what is the probability that opening night ticket sales are more than $1620?
Z = (score-mean)/SD
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.