bellcurve wrote:

I have a clearifying question about set theory formulas, if you all don't mind.

1. For 3 sets A, B, and C: P(AuBuC) = P(A) + P(B) + P(C) – P(AnB) – P(AnC) – P(BnC) + P(AnBnC)

2. No of persons in atleast one set = P(A) + P(B) + P(C) - P(AnB) - P(AnC) - P(BnC) + 2 P(AnBnC)

Why these two formulas are different? Isn't "at least in one set" equal to union of all (AuBuC)?

Thanks,

BC

I think first one is good for at least one person as well.

No idea where can we use the second formula.

_________________

~fluke

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