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Chapter 7: Probability
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Figure 7-8:
Venn diagram for A
B or (A or B)
(Shaded area within the two circles)
Example 7-12:
A game show wheel has ten numbers listed from 1 to 10.
Define
A
to be the event of spinning the wheel and it stops on an even
number. Define
B
to be the event of rolling a fair standard six-sided die and
observing the number on the up-turned face. What are the elements of
A
B
?
Solution:
Based on the definition of the events, then
A
= {2, 4, 6, 8, 10}
and
B
= {1, 2, 3, 4, 5, 6}. Thus,
A
B
= {1, 2, 3, 4, 5, 6, 8, 10}. Note that
elements that are common to both
A
and
B
are not repeated when listing the
elements in
A
B
. The union is shown in
Figure 7-9
.