statistics
posted by Daniel on .
Starting with a population that is normally distributed with a mean of 100 and a standard deviation of 12, answer the following questions (if possible).
a. What is the probability of randomly drawing a single score between 100 and 106, p(100 < X < 106)?
b. What is the probability of drawing a random sample of 9 observations with a mean between 100 and 106, p(100 < M < 106)?
c. What is the probability of drawing a random sample of 36 observations with a mean between 100 and 106, p(100 < M < 106)?

a. Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to the Z scores calculated.
b, c. Z = (scoremean)/SEm
SEm = SD/√n
Use the same table.