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Chapter 9: The Normal Probability Distribution
Figure 9-34:
Area and probability value for
P
(
X
109)
Example 9-11:
Suppose annual starting salaries for full time nurse
practitioners graduates are normally distributed with a mean of $83,400 and
a standard deviation of $19,300. What is the probability that a recent nurse
practitioner graduate will earn a starting salary between $72,000 and
$89,000?
Solution:
Let
X
= annual starting salary. Then the random variable
X
will
be normally distributed with a mean of 83,400 and a standard deviation of
19,300. Based on the problem, we need to find
P
(72,000
X
89,000).
Using the
Normal Probability Distribution
workbook to solve, we get
the
value of 0.3368. The result is shown in
Figure 9-35
.
Click here for the Normal Probability Distribution Workbook