1. The document discusses probabilities of disjoint and overlapping events. 2. It provides examples to illustrate disjoint events which have no common outcomes, and overlapping events which have one or more common outcomes. 3. It also discusses complementary events, which are disjoint events where one event or the other must occur, and their probabilities sum to 1.

1. 11.8 Probabilities of Disjoint
and Overlapping Events
esson Title: 11.8 Probability of Disjoint and Overlapping Events Lesson Title: 11.8 Probability of Disjoint and Overlapping
Objective: The students will be able to find the probability that Events
vent A or B occurs.
Method: April 26, 2011 Objective: The students will be able to find the probability
that event A or B occurs.
1. Show the students how to use a venn diagram to explain Method:
how events occur. Show the difference between disjoint 1. Review the homework with the students.
events and overlapping events. 2. Allow the students to ask any questions that they
2. Next have the students complete an example where they may have from the homework.
have to decide whether two events are disjoint or 3. Go over more practice problems with the students.
overlapping. A: 11.8 odd
3. Explain to the students how to find the probability of disjoint
events.
4. Next, explain to the students how to find the probability of
overlapping events.
5. Lastly, explain complementary events. Show the students
how to find the probability of complementary events.
6. Give the students several examples to practice.
: 11.8 even

4. Disjoint Events or Mutually Exclusive
Events: events that have no common
outcomes.

5. Disjoint Events or Mutually Exclusive
Events: events that have no common
outcomes.
Overlapping Events: events that have
one or more outcomes in common.

7. Example 1:

8. Example 1:

9. Example 1:

13. Example 2:

14. Example 2:

19. Example 3:

20. Example 3:

22. Two events are complementary
events if they are disjoint events and one
event or the other must occur.

23. Two events are complementary
events if they are disjoint events and one
event or the other must occur.
The sum of the
probabilities of t wo
complementary
events is 1.

24. Two events are complementary
events if they are disjoint events and one
event or the other must occur.
P(not A) = 1
- P(A) The sum of the
probabilities of t wo
complementary
events is 1.

25. Example 4:

26. Example 4: