Question

Camila earned a score of 668 on Exam A that had a mean of 600 and a standarddeviation of 40. She is about to take Exam B that has a mean of 700 and a standarddeviation of 100. How well must Camila 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

7tszs, this is the solution to the exercise:

Step 1: Like the scores of the exams are normally distributed, let's calculate the z-score for the score Camila earned on Exam A, this way:

• z-score = (Score - Mean)/Standard deviation

z-score = (668 - 600)/40

z-score = 68/40

z-score = 1.7

Step 2: Now, we need to calculate the exam score for identical z-score = 1.7 on Exam B, as follows:

• z-score = (Score - Mean)/Standard deviation

Replacing by the values we know:

1.7 = (Score - 700)/100

1.7 * 100 = Score - 700

170 = Score - 700

Score = 700 + 170

Score = 870

Therefore, Camila should earn a score of 870 on Exam B to do equivalently well as she did on Exam A.