Question 928579
         X      Y      Tot

A    24     31      55

B    13     66      79

Tot  37     97     134

Is P(X or A) = (37 + 55 - 24)/134 = 68/134?

and

Is P(X|A) = P(X and A)/P(A) = 24/55?
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Both are correct.
Cheers,
Stan H.
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