Practice Problem Answers: z-scores

Item 1

Calculate the z-score, assuming:

X = 10
mean = 50
stdev = 10  

X – mean = - 40 
z score = - 4.0

 

Item 2

Calculate the z-score, assuming:

X = 80
mean = 50
stdev = 15  

X – mean = 30
z score = 2.0

 

Item 3

Calculate the z-score, assuming:

X = 112
mean = 100
stdev = 15  

X – mean = 12
z score = .80

 

Item 4

Calculate the raw score, assuming:

z = 1.5
mean = 115
stdev = 10

z * stdev = 15
X = 130

 

Item 5

Calculate the raw score, assuming:

z = -1.37
mean = 100  

stdev = 20
z * stdev = 27.4
X = 72.6

 

Item 6

Calculate the raw score, assuming:

z =  2.54
mean = 80
stdev = 20  

X = 130.8
2.54*20 = 50.8
50.8 + 80 = 130.8

 

NOW YOU CHOOSE:
    Day 4: z-Score
    A Bit More About z-Scores
    Even More About z-Scores
    How To Calculate z-Scores
    Practice Problems
    Basic Facts About z-Scores
    Vocabulary
    Formulas For z-Scores
    Quiz 4
    Summary