Probability and Z-Scores

Find the Z-score.

Mean = 22

Standard Deviation: 3.1

x = 29

• 2.26

• 16.45

• -2.26

• 1.26

Find the Z-score.

Mean = 21

Standard Deviation: 1.3

x = 22

• 0.77

• 5.33

• 1.07

• 1.26

Find the z-score.

Mean = 40

Standard Deviation: 1.4

x = 42

• 1.43

• 1.28

• -1.4

• 1.24

If heights of 3rd graders follow a normal distribution with a mean of 52 inches and a standard deviation of 2.5 inches, what is the z score of a 3rd grader who is 47 inches tall? 

• -5
• -2
• 2
• 5

The mean temperature in Glens Falls for the month of February is 23 degrees with a standard deviation of 4.2 degrees.  What is the z-score for a temperature of 17 degrees?  

• 1 
• 1.43
• -1.43
• 11.5

• 298

• 296

• 220

• 380

Steve took his math test and scored an 88. If the class average was a 78 with a standard deviation of 5, what percent of students earned a grade that was higher than Steve's grade?

• 97.5%

• 93%

• 5%

• 2.5%

• It means you did better than zero people.

• It means you scored the same grade as the average grade.

• It means you earned a zero on the quiz.

• It means the average score was a zero.

Use the image of the normal graph provided. What is the value of the mean?

• 6

• 34

• 52

• 70

Use the image of the normal graph provided. What is the value of the standard deviation?

• 6

• 12

• 36

• 18