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Chapter 8: Discrete Probability Distributions
Figure 8-20:
Display of the Experimental Design for
Example 8-18
Let the number of trials on which the first incorrect answer occurs be
denoted by the random variable
X
. Then
X
is a geometric random variable
with
= 4, and
= 0.75. Substituting into the formula, gives
That is, the probability of guessing the first incorrect answer on the fourth
guess in this geometric experiment is 0.0117, correct to four decimal places.
Figure 8-21 s
hows the results from the
Geometric Distribution
workbook.