Question 1183409
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Use this probability identity


    P(A U B) = P(A) + P(B) - P(A and B).


In your case it becomes


    0.7 = 0.6 + 0.5 - P(A and B)


and gives


    P(A and B) = 0.6 + 0.5 - 0.7 = 0.4.      <U>ANSWER</U>
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Solved and explained.