Question

For a normal population with a mean of m = 80 and a standard deviation of s = 10, what is the probability of obtaining a sample mean greater than m = 75 for a sample of n = 25 scores? p = 0.0062 p = 0.9938 p = 0.3085 p = 0.6915

Answer 1

what do pre and post test studies look at?data collected on the same sample elements before and after some experiment is performedwhen are the t procedures exactly correct?when the pop is exactly Normal (rare)the t procedures are robust to small deviations from Normality, butthe sample must be a random sample from the pop