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Chapter 7: Probability
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Figure 7-14:
Venn diagram depicting two mutually exclusive
events
A
and
B
Rule 5:
If two events
A
and
B
are mutually exclusive, then
P
(
A
B
) =
P
(
A
) +
P
(
B
).
Notes:
If two events are mutually exclusive, then if one of them occurs, the
other cannot occur.
Another term used for mutually exclusive is disjoint.
Example 7-16:
Items are being selected from a production line. Let
D
be
the event of a defective item being selected. Let
N
be the event of a non-
defective item being selected. Are these mutually exclusive events?
Solution:
These events are mutually exclusive, since, when an item is
selected, that item will be either classified as defective or non-defective.
There is no commonality to these two events.