Normal Distribution, Z-Score

Joanne's score on a test gives her a Z-score is -1.50. What does this mean?

• Joanne didn't take the test yet.

• Joanne's test score is 1.50 standard deviations below the average test score.

• Joanne did better than 1.50 times her peers.

• Joanne's test score, on average, was 1.5 points lower than the other test scores.

So if Tina's Z-score is +2.00 and Paula's Z-score is +1.09, who performed better?

• Tina's performance is farther above the mean so she did better.

• Paula's score is closer to the mean so she did better.

• They both did the same.

On a standardized exam, the scores are normally distributed with a mean of 500 and a standard deviation of 25. Find the z-score of a person who scored 525 on the exam.

• 1

• -1

• 0

• 2

On a standardized exam, the scores are normally distributed with a mean of 51 and a standard deviation of 10. Find the z-score of a person who scored 27 on the exam.

• -2.4

• 2.4

• 1.51

• -1.51

On a standardized exam, the scores are normally distributed with a mean of 400 and a standard deviation of 40. Find the z-score of a person who scored 472 on the exam.

• 1.8

• -1.8

• 0.76

• -0.76

On a standardized exam, the scores are normally distributed with a mean of 300 and a standard deviation of 20. Find the z-score of a person who scored 294 on the exam.

• -0.3

• 0.5

• 0.3

• 0.95

On a standardized exam, the scores are normally distributed with a mean of 300 and a standard deviation of 40. Find the z-score of a person who scored 400 on the exam.

• 2.5

• 25

• 2.5%

• -2.5

On a standardized exam, the scores are normally distributed with a mean of 750 and a standard deviation of 100. Find the z-score of a person who scored 580 on the exam.

• -1.7

• 1.7%

• 1.12

• 1.7

On a standardized exam, the scores are normally distributed with a mean of 36 and a standard deviation of 5. Find the z-score of a person who scored 39 on the exam.

• 0.6

• -0.6

• 0.79

• -0.79

On a standardized exam, the scores are normally distributed with a mean of 75 and a standard deviation of 10. Find the z-score of a person who scored 45 on the exam.

• -3

• 3

• 1.44

• 2