Z-Scores & Z-tables

A data set has a mean of 290 and a standard deviation of 20. Calculate the z-score for 265.

• $z=250.5$

• $z=1.25$

• $z=-1.02$

• $z=-1.25$

Tags

CCSS.HSS.ID.A.4

A data set has a mean of 20 and a standard deviation of 3. Calculate the z-score for 23.

•  $z=-1$  

•  $z=16.33$  

•  $z=1$  

•  $z=3$  

Tags

CCSS.HSS.ID.A.4

A data set has a mean of 300 and a standard deviation of 40. What value would have a z-score of  $z=-2$  ?

• 298

• 296

• 220

• 380

Tags

CCSS.HSS.ID.A.4

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%

Tags

CCSS.HSS.ID.A.4

What does it mean to have a z-score of  $z=0$  on a quiz?

• 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.

Tags

CCSS.HSS.ID.A.4

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

• 6

• 34

• 52

• 70

Tags

CCSS.HSS.ID.A.4

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

• 6

• 12

• 36

• 18

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.ID.A.2

Use the image of the normal graph provided. What percent of values are less than 46?

• 16%

• 84%

• 46%

• 12.5%

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.ID.A.1

What percent of scores are below a z-score of  $z=-1.02$ ?  (Use either the attached image of a z-table or use your own copy of the z-table from your notes)

• 15.87%

• 15.39%

• 9.68%

• 84.61%

Tags

CCSS.HSS.ID.A.4

What percent of scores are below a z-score of  $z=2.34$ ?  (Use either the attached image of a z-table or use your own copy of the z-table from your notes)

• 99.04%

• 0.96%

• 98.93%

• 97.68%

Tags

CCSS.HSS.ID.A.4