Ramones’s Chemistry test was much better as it has higher Z-Score than history
For History test, Test score (x) = 40
Mean (μₓ) = 30, Standard deviation (σₓ) = 10
For Chemistry test, Test score (Y) = 40
Mean (μ) =30, Standard deviation (σ) =5
Ramones’s Z-score for History test is given by,
Z-Score = (x-μₓ)/σₓ =(40-30)/10 = 1
Ramones’s Z-score for chemistry test is given by,
Z-Score = (y-μ)/σ =(40-30)/5 = 2
Thus, Ramones’s Chemistry test was much better, because Chemistry test has higher z-score.
Difference in the mean score (α) =μₓ -μ =0
Difference in Z-Score= Z- Zₓ =1
To learn more about Z-Score visit:
https://brainly.com/question/25638875
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