Probability Formulas
0 ≤ p(A) ≤ 1
p(S) = 1
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Probability Formula
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Addition Rule
If A
B ≠
.
p(A
B) = p(A) + p(B) − p(A
B)
p(A
B
C) = p(A) + p(B) + p(C) − p(A
B) − p(A
C) − p(B
C) + p(A
B
C)
Multiplication Rule
Independent Events
p(A
B) = p(A) · p(B)
Dependent Events
p(A
B) = p(A) · p(B|A)
Conditional Probability

Independent Events
p(A|B) = p(A)
Dependent Events
p(A|B) ≠ p(A)
Law of Total Probability
p(B) = p(A1) · p(B|A1) + p(A2) · p(B|A2 ) + ... + p(An) · p(B|An )
Bayes' Theorem
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Expected Value
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Variance of a Discrete Random Variable
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Standard Deviation of a Discrete Random Variable

Binomial Distribution
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Normal Approximation to the Binomial
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