a) Z-score for Patrisse test grade is 0.7288
b) z-score for Makayla test grade is -0.7441
c) Patrisse did better.
<h3>What is z- score?</h3>
A Z-score is a numerical measurement that describes a value's relationship to the mean of a group of values.
Z-score for Patrisse test grade.
X= 81.4, = 72.8, = 11.8
Z= x- /
Z= 81.4 - 72.8/ 11.8
Z= 0.7288
Now, z-score for Makayla test grade.
X= 60.6, = 67, = 8.6
Z= x- /
Z= 60.6 - 67/ 8.6
Z= -0.7441
Hence, Patrisse did better as she had better z- score.
Learn more about this concept here:
brainly.com/question/23261840
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