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Noah got 92 on Exam I in Math 150. The scores of Noah's class have a mean of 81 and astandard deviation of 5.1. Amelia got 88 on Exam I in Math 302. The scores of Amelia'sclass have a mean of 72 and a standard deviation of 4.9. Who is having a relatively highlyscore? Noah or Amelia?

User Hager
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1 Answer

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Noah's score = 92

Noah's class mean = 81

Noah's class standard deviation = 5.1

Thus, his z-score his calculated as;


\begin{gathered} z=(x-\mu)/(\sigma) \\ \text{Where }\mu=\operatorname{mean} \\ \sigma=\text{ standard deviation} \end{gathered}

Thus, for Noahs', we have;


\begin{gathered} z=(92-81)/(5.1) \\ z=(11)/(5.1) \\ z=2.1569 \end{gathered}

Also, similarly for Amelia, we have;


\begin{gathered} z=(88-72)/(4.9) \\ z=(16)/(4.9) \\ z=3.2653 \end{gathered}

From the results above, Amelia's z-score is higher than that of Noah. Thus, Amelia relatively has the higher score.

User Akarve
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