posted by Anonymous .
Calculate the z-score for each set of data. Determine who did better on her respective test, Tonya or Lisa.
Student English Test Grade z-Score Student Math Test Grade z-Score
John 82 Jim 81
Julie 88 Jordan 85
Samuel 90 Saye 79
Tonya 86 Lisa 82
Mean 86.50 81.75
St. Dev. 3.42 2.50
Given the above information, predict the raw score for a student whose z-score in the Math test is .98.
Didn't I answer this for you previously?
Z = (score-mean)/SD
Compare the Z scores for Tonya and Lisa.
For second question, substitute .98 for the Z score and solve for the raw score. (Are you sure that .98 = Z score and not a proportion of the scores? If so, find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion (.98) and its corresponding Z score. Again, use the equation above.