Question 644:

Asked on March 3, 2009

Tags: Z-Score

1

Answer:

No answer provided yet.To answer this question we need to use the formula for a z-score around a single data-point.  The formula is (data-point-mean )/standard deviation. For the 1st test score, we have (232-220)/10, which gives us a z-score of 1.2. For the second score we get a z-score of (212-220)/10 =  -0.8. The second z-score is negative because the raw score of 212 is below the mean of 220.  We'd say these raw scores are 1.2 standard deviations above the mean and .8 standard deviations BELOW the mean.