Question

Addison earned a score of 510 on Exam A that had a mean of 550 and a standarddeviation of 40. She is about to take Exam B that has a mean of 26 and a standarddeviation of 5. How well must Addison score on Exam B in order to do equivalentlywell as she did on Exam A? Assume that scores on each exam are normallydistributed

Answer 1

Exam A:

`\begin{gathered} \text{Score (x)=510} \\ \mu\text{ (mean)=55}0 \\ \sigma\text{ (standard deviation)=40} \end{gathered}`

`\begin{gathered} Z\text{ = }\frac{x\text{ -}\mu}{\sigma} \\ Z\text{ = }(510-550)/(40)=-1 \end{gathered}`

Z = -1, then...

Exam B:

`\begin{gathered} x\text{ = ?} \\ \mu=26 \\ \sigma=5 \end{gathered}`
`x=Z*\sigma+\mu=-1*5+26=21.00`

Answer: 21