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

1 answer

Z = (score-mean)/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.