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QUESTION

If $p(A)=0.6,\ p(B)=0.5$ and $p(A$ and $B)=0.7$ what is $p(A$ or
$B)$?

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ANSWER

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




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