kris scored 630 points on a particular section of a CPA exam for which the score were normally distributed with a mean of 600 points and a standard deviation of 75 points. At a differenttime, kerry scored 540 points on the same section, for which scores were normally distributed with a mean of 500 points and a standard devaition of 30 points.

Calculate kris's z-score.
Calculate kerry's z-score.
Who scored higher relative to the norms?

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Z = (score-mean)/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.

To calculate each person's z-score, we use the formula:

z = (x - mean) / standard deviation

1. Kris's z-score:
Given: x = 630, mean = 600, standard deviation = 75
z = (630 - 600) / 75
z = 30 / 75
z = 0.4

2. Kerry's z-score:
Given: x = 540, mean = 500, standard deviation = 30
z = (540 - 500) / 30
z = 40 / 30
z = 1.333

To compare who scored higher relative to the norms, we look at the z-scores. The higher the z-score, the further above the mean the score is. Therefore, Kerry scored higher relative to the norms since his z-score is higher than Kris's z-score.