10.5 Independent Events Objective: Find the probability of 2 or more independent events.

10.5 Independent Events

Objective: Find the probability of 2 or more independent events.

2 events are INDEPENDENT if the occurrence or non-occurrence of one event has NO effect on the likelihood of the occurrence of the other event.

If the occurrence or non-occurrence of one event DOES affect the occurrence of the other event, then the events are DEPENDENT.

Ex 4

7. A number cube is rolled twice. Compare the following problems:1) Find the probability that the first roll is four and the

second roll is even.2) Find the probability that the first roll is four or the

second roll is even.

1) P( 4) and P(even) =

81

21

41

)()(

BPAP

2) P( 4) or P(even) =

43

21

41

)()(

BPAP

Review of Independent Events

10.6 Dependent Eventsand

Conditional Probability

Objective: Find conditional probabilities.

KNOWING THE OUTCOME OF ONE EVENT CAN AFFECT THE PROBABILITYOF ANOTHER EVENT.

SOMETIMES THE PROBABILITY OF THE SECOND EVENTCHANGES DEPENDING ON THE OUTCOME OF THE FIRST EVENT.

.75

.6

.1554

.30

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