Z-Scores
A z-score says how many standard deviations a value is from the mean: z = (x - mean) / sd. It lets you compare values from different scales. A mark of 78 in an exam averaging 65 (sd 8) has a z-score of about 1.6. A mark of 90 in a different exam averaging 80 (sd 10) has a z-score of 1.0. The first is the more impressive result.
Examplepython
Quick check
A z-score of 0 means the value is...
Your turn: write the code
Print the z-score of a value 130 when the mean is 100 and the standard deviation is 15.
Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.
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