9.7 Probability of Multiple Events 2011
January 24, 2011
Warm ­ Up
1. There are 36 different ways to roll 2 dice. 18 of them result in an odd sum and 15 of them result in a prime sum. a. What is the probability of rolling an odd sum? b. A prime sum?
2. A bag contains twenty $1 bills, ten $5 bills, five $10 bills, three $20 bills, and one $100 bill. If you pick one bill at random, find each.
a. the sample space
b. P($100)
c. P($100 or $20)
d. P(not $1)
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9.7 Probability of Multiple Events 2011
January 24, 2011
9.7 Probability
of Multiple
Events
OBJ: Find the probability of
event A AND B.
Find the probability of
event A OR B
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9.7 Probability of Multiple Events 2011
Mr. Aweida
January 24, 2011
Vs.
P(odd & prime)
P(odd or prime)
10
Points
Points
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9.7 Probability of Multiple Events 2011
January 24, 2011
Classifying Events
When the outcome of one event does not affect the outcome of a second event, the two events are independent events.
When the outcome of one event does affect the outcome of a second event, the two events are dependent events.
?
So did the rolling the dice game have independent or dependent events?
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9.7 Probability of Multiple Events 2011
January 24, 2011
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9.7 Probability of Multiple Events 2011
January 24, 2011
What is the P(A and B)?
Event A
Event B
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9.7 Probability of Multiple Events 2011
January 24, 2011
Event A
Event B
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9.7 Probability of Multiple Events 2011
EXAMPLE
January 24, 2011
Chauncey Billups is playing a friendly game of poker. He will win the hand if the next card is either less than 8 or greater than a Jack. There is a 53% chance the next card is less than 8 and 34% chance its greater than a Jack. What is the probability Chauncey will win the hand?
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9.7 Probability of Multiple Events 2011
EXAMPLE
January 24, 2011
Suppose you reach into the bowl and select a piece of fruit at random. What is the probability that the fruit is green or an apple?
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9.7 Probability of Multiple Events 2011
January 24, 2011
P(homework) = 100%
Homework: pg. 534 1­4, 5,11,12, 15­25 odd, 31­35 odd)
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9.7 Probability of Multiple Events 2011
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