Find the probability that the score will be less than 90.0
Individual scores of a placement examination are normally distributed with a mean of 84.2 and a standard deviation of 12.8.
If the score of an individual is randomly selected, find the probability that the score will be less than 90.0.
If a random sample of size n = 20 is selected, find the probability that the sample mean will be less than 90.0.
