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Discuss the conditions under which P(A or B)= P(A) + P(B) is true

User MCMastery
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That condition is true if P(A) and P(B) are independent of one another. For example, if I was pulling marbles out of a bag, if I am replacing the marbles back after I pull one out, then P(A or B) = P(a)+P(B).
User Thibault Witzig
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