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Chapter 9: The Normal Probability Distribution
Solution:
This is equivalent to finding
P
(
1.35).
Using the
Normal Probability Distribution
workbook to solve, we get
the
value of 0.0885. Thus,
P
(
1.35) = 0.0885. The result is shown in
Figure 9-22
.
Figure 9-22:
Area and probability value for
P
(
z
1.35)
Again, one can use a standard normal distribution tables for
= 1.35. When
you look up the
-value = 1.35, the corresponding area under the curve from
0 to 1.35 is 0.4115. Since the total area under the curve is 1 and because of
the symmetry of the distribution, the total area to the right of 0 will be equal
to 0.5. Thus, the required area for
P
(
1.35) = 0.5 – 0.4115 = 0.0885.
This is shown in
Figure 9-23
.
Click here for the Normal Probability Distribution Workbook