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Probability of an event
with a
finite
sample space having
equally likely outcomes
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Consider a fair die. What is the probability
that the outcome is divisible by 3?
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Consider a fair die. What is the probability
that the outcome is divisible by 3?
Let A be the event that the outcome is divisible by 3
By the third axiom of a probability,
6
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Consider a fair die. What is the probability
that the outcome is divisible by 3?
If we denote the number of elements in an event B by
n(B), then
n(S) = 6
,
n(A) = n({3,6}) = 2
, and n({i}) = 1, for i=1,2,…,6.
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n(A)
n(S)
sample space
for an experiment contains
•
finite, say N, elements
,
•
all of which are
equally likely to occur
,
then the
probability of any event A, denoted by P(A),
containing n
of these N sample points is the ratio of the
number of elements in A to the number of elements in S
,
i.e.
.
)
(
N
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This note was uploaded on 12/09/2010 for the course ENGLISH 1303 taught by Professor May during the Spring '10 term at HKU.
 Spring '10
 may
 English

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