Posted by Cookie on .
For a population with a mean of μ 70 and a standard
deviation of 20, how much error, on average,
would you expect between the sample mean (M) and
the population mean for each of the following sample
sizes?
a. n 4 scores
b. n 16 scores
c. n 25 scores

Statistic 
PsyDAG,
Z = (scoremean)/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 related to the Z scores.