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QUESTION

If $p(A)=0.4,\ p(B)=0.7$ and $p(A$ and $B)-0.6$, find $p(A$ or
$B)$.

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ANSWER

$p(A$ or $B)=p(A)+p(B)-p(A$ and $B)=0.4+0.7-0.6=0.5$




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