4. Z = standardized normal variable.
Notation used:
Z = standardized normal variable.
 = 0 and  = 1 are the basic values for
mean and standard deviation.
 is the symbol often used for the mean
of a normal distribution.
X = mean (or arithmetic mean) when
analyzing general data.

5. The Greek Alphabet

6. Area under the Standard Normal Curve:
The area represents the probability (percent
of data) for a given interval of the normal distribution.
Calculator commands
we will use today:
2nd DISTR
2:normalcdf(lower, upper,  ,)
3:invNorm(probability,  , )
The calculator always
measures to the left
of the z-value.

7. 3. Sketch two normal curves:
b. μ = 75 σ = 5

8. 6. given: μ = 550 σ = 35 b. P(515 < X < 585) a. sketch curve:
c. P(X) = 99.7% Find the interval.
d values in data set…how many are between 480 & 620?

9. 7. given: 500 values normally distributed and μ = 24 σ = 2
a. P(22 < X < 26)
b. P(20.5 < X < 27.5)
c. P(X) = 50% Find the interval.

10. 7. given: 500 values normally distributed and μ = 24 σ = 2
c. P(X) = 50% Find the interval.