Z-Scores

What is the purpose of z-scores?

• to describe the exact location of a score within a distribution

• to find the mean of the distribution

• to describe the shape of the distribution

• to find the standard deviation of the distribution

Tags

CCSS.HSS.ID.A.4

What is the formula to find the z-score for population?

• z=X-M

• z=σ-M/μ

• ^z/M=μ

• z=X-μ/σ

Tags

CCSS.HSS.ID.A.4

The sign of the z-score indicates whether the location is above(positive) or below(negative) the mean.

• True

• False

Tags

CCSS.HSS.ID.A.4

Find the z-score value corresponding if the location is below the mean by 2 standard deviations

• +2.00

• -2.00

• +1.25

• -1.00

Tags

CCSS.HSS.ID.A.4

Find the z-scores value corresponding if the location is above the mean by 1/2 standard deviations

• -0.50

• +1.00

• +0.50

• -1.00

Tags

CCSS.HSS.ID.A.4

The average waist size for teenage males is 29 inches with a standard deviation of 2 inches. 
If waist sizes are normally distributed, determine the z-score of a teenage male with a 33 inch waist.  

• 2
• 1
• -2
• -1

Tags

CCSS.HSS.ID.A.4

What shape is a normal distribution curve?

• Half curve
• Round curve
• Bell curve
• Square curve

Tags

CCSS.HSS.ID.A.3

The z-score represents.....

• the amount of standard deviations a data value is above or below the mean.
• the percentile the data value is above or below the mean.
• the amount of standard deviations a data value is above or below the median.
• the percent the data value is above or below the mean.

Tags

CCSS.HSS.ID.A.4

μ = 70 , σ = 8 , X = 50 . Find z score

• 2.5
• -2.5
• 5.2
• -5.2

Tags

CCSS.HSS.ID.A.4

What is the z-score for the mean?

• -1

• +1

• 0

• It doesn't have one!

Tags

CCSS.HSS.ID.A.4