Find probability of disjoint events

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EXAMPLE 1
Find probability of disjoint events
A card is randomly selected from a standard deck
of 52 cards. What is the probability that it is a
10 or a face card?
SOLUTION
P(A or B) P(A) P(B)
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EXAMPLE 2
Standardized Test Practice
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EXAMPLE 2
Standardized Test Practice
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EXAMPLE 3
Use a formula to find P(A and B)
SOLUTION
Let event A be selecting a senior who is a
varsity athlete and event B be selecting a senior
on the honor roll. From the given information you
know that
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EXAMPLE 3
Use a formula to find P(A and B)
Find P( A and B )
Write general formula.
Substitute known probabilities.
Solve for P(A and B).
Simplify.
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for Examples 1, 2, and 3
GUIDED PRACTICE
A card is randomly selected from a standard deck
of 52 cards. Find the probability of the given
event.
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for Examples 1, 2, and 3
GUIDED PRACTICE
8
for Examples 1, 2, and 3
GUIDED PRACTICE