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Nevaeh earned a score of 508 on Exam A that had a mean of 500 and a standarddeviation of 40. She is about to take Exam B that has a mean of 350 and a standarddeviation of 20. How well must Nevaeh score on Exam B in order to do equivalentlywell as she did on Exam A? Assume that scores on each exam are normallydistributed

Nevaeh earned a score of 508 on Exam A that had a mean of 500 and a standarddeviation-example-1
User CuCaRot
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First we must obtain the relationship between the grade, the mean and the standard deviation of exam A


\begin{gathered} z=\frac{x-\operatorname{mean}}{\sigma} \\ z_A=(508-500)/(40) \\ z_A=0.2 \\ \end{gathered}

Now we have to find the required score for exam B to reach the same ratio factor z


\begin{gathered} z_B=z_A \\ 0.2=\frac{x_B-350_{}}{20} \\ x_B=0.2(20)+350 \\ x_B=354 \end{gathered}

As seen in the calculations, Nevaeh must score 354 on Exam B to equal the score on Exam A

User Mcnk
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