Question 1145218
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    P(A or B) = P(A) + P(B) - P(A and B)


This universal formula of Probability theory is valid ALWAYS, for any events A and B.


Substitute the given data and calculate.


    P(A or B) = 0.50 + 0.30 - 0.15 = 0.65.    <U>ANSWER</U>
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