350 / 762
350
Chapter 8: Discrete Probability Distributions
Solution:
Let
X
= number of defectives in the sample. From the data given
in the problem,
= 30,
= 5,
k
= 2,
= 1,
–
= 30 – 2 = 28, and
–
= 5 – 1 = 4. The display of the different components for the data is given in
Figure 8-27
.
Figure 8-27:
Display of the different components for
Example 8-21
Using the formula to compute the probability of exactly one defective in the
sample of size 5 is
Thus, the probability of exactly 1 defective in the sample of size 5 is 0.2874,
correct to four decimal places. That is, a lot of 30 components has a 28.74%
chance of being rejected.
Figure 8-28
shows the output from the
Hypergeometric Distribution
workbook with
P
(
X
= 1) = 0.2874.