Find unknown event given its conditional probabilities

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If it is known that: $P(A)=0.65, P(B)=0.25 , P(C)=0.10$ And that: $P(X|A)=0.15, P(X|B)=0.25, P(X|C)=0.85$

How would one solve for $P(X)$?

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If $A, B, C$ are mutually exclusive and exhaustive, we can find $P(X)$ by

$P(X) = P(A)P(X|A) + P(B)P(X|B) + P(C)P(X|C)$

$P(X) = 0.65 \times 0.15 + 0.25 \times 0.25 + 0.1 \times 0.85$

$P(X) = 0.245$