Using the normal curve

Chapter 4 Normal Curve and Standard Scores

Practice with the Normal Curve

The Normal Curve Using the z-Table

100%

The Normal Curve

50

50%

50th percentile

The Normal Curve

s (standard deviation)

z-score

-2

-1

0

1

2

-2

-1

0

1

2

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2

50% 16%

2.5%

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2

84% 97.5%

The Normal Curve

50

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2

84% 97.5%

16%

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2

Mean + 1 s = 68%

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2

Mean + 2 s = 95%

The Normal Curve

2.5

s (standard deviation) z-score

13.5

34

34

13.5

-2

-1

0

1

2

-2

-1

0

1

2

2.5

The Normal Curve

2.5

s (standard deviation)

z-score

13.5

34

34

13.5

2.5

-2

-1

0

1

2

-2

-1

0

1

2