If n

Finally the standard error of M

= 2.35.

Once you know the mean and the standard error of the sampling distribution of the difference between means, you can answer questions such as the following: If an experiment with the memory drug just described is conducted, what is the probability that the mean of the group of 10 subjects getting the drug will be 15 or more points higher than the mean of the 8 subjects not getting the drug? Right away it can be determined that the chances are not very high since on average the difference between the drug and no-drug groups is only 10.