Three students take equivalent stress tests. Which is the highest relative score?

a. A score of 144 on a test with a mean of 128 and a standard deviation of 34.
b. A score of 90 on a test with a mean of 86 and a standard deviation of 18.
c. A score of 18 on a test with a mean of 15 and a standard deviation of 5.

2 answers

Z = (score-mean)/SD

The highest Z score has the highest relative score.
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