In: Statistics and Probability
James scored 68 on his English class final and was devastated by his failing grade. His class distribution had a mean of 55 and a standard deviation of 6. Matt was quite proud of his score of 88 for his Spanish language class. His class distribution had a mean of 98 with a standard deviation of 7. Who did better relative to their class?
For James
Z-score = X - Mean / standard deviation
= 68 - 55 / 6
= 2.17
For Matt
Z-score = X - Mean / Standard deviation
= 88 - 98 / 7
= -1.43
Z score for James is greater than Z score for Matt.
So, James did better relative to their class.