, n
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MATHEMATICS
Therefore,
P (A) = P (E1) P (A|E1) + P (E2) P (A|E2) + + P (En)P(A|En)
or
P(A) =
1
P(E )P(A|E )
n
j
j
j=∑
Example 15 A person has undertaken a construction job The probabilities are 0 65
that there will be strike, 0