Use the information on the right to determine which students will have positive z-scores.

a) aaliyah, who completed the exam in 55 minutes
b) benjamin, who completed the exam in 86 minutes
c) cynthia, who completed the exam in 72 minutes

cynthia’s z-score is:

Benjamin and Cynthia will have positive z-scores

Cynthia’s z-score is: 0.2

Step-by-step explanation:

The z-scores give us information about how many standard deviations from the mean a data is found. This difference can be negative, if the data is n deviations to the left of the mean, or it can be positive if the data is n deviations to the right of the mean.

To calculate the Z scores we calculate the difference between the value of the data and the mean and then we divide this difference between the standard deviation.

Thus:

.

Where x is the value of the data, μ is the mean and σ is the standard deviation

Aaliyah, completed the exam in 55 minutes.

So

then the z score will be negative

Benjamin, completed the exam in 86 minutes

then the z score will be positive

Cynthia, completed the exam in 72 minutes

then the z score will be positive

Benjamin and Cynthia will have positive z-scores