1. Z = (score-mean)/SD
2. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to the Z score. Multiply proportion by 100 to get percentage.
3. Precentile rank is percentage ≤ the score. Use same table.
A set of data is normally distributed with a mean of 200 and standard deviation of 50.
• What would be the standard score for a score of 250?
• What percentage of scores is between 200 and 250?
• What would be the percentile rank for a score of 250?
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