how to calculate the probability of a sample mean?
['by converting the.', 'to a z-value and finding probabilities using the Z-table (see below). ... ', 'Substituting the appropriate values of the mean and standard error of.', 'the conversion formula becomes:', "Don't forget to divide by the square root of n in the denominator of z. ... ", 'As X has a normal distribution to start with, you know.']