Question

aLevi earned a score of 710 on Exam A that had a mean of 700 and a standarddeviation of 25. He is about to take Exam B that has a mean of 200 and a standarddeviation of 50. How well must Levi score on Exam B in order to do equivalently wellas he did on Exam A? Assume that scores on each exam are normally distributed.

Answer 1

Answer: 220

First, let us find the z-score of Levi's score on Exam A using the formula,

`z=(x-\mu)/(\sigma)`

From the given, we know that:

x = 710

μ = 700

σ = 25

Substituting this to the formula,

`z=(x-\mu)/(\sigma)\Rightarrow z=(710-700)/(25)=0.4`

We will now use this z-score to find Levi's score on Exam B

Exam B has:

μ = 200

σ = 50

`z=(x-\mu)/(\sigma)\Rightarrow0.4=(x-200)/(50)`
`0.4=(x-200)/(50)\Rightarrow(0.4)(50)=x-200\Rightarrow20=x-200`
`20=x-200\Rightarrow x=20+200=220`

Therefore, Levi must score 220 to do equivalently well as he did on Exam A.