i got 7/12
1/4 + 1/3 + 1/6 = 9/12
Mike or Bob win the championship
1/4 + 1/3 = 3/12 + 4/12 = 7/12
Well done cocosdreamland ! but you forgot to subtract the event for Ben winning.
p(A or B but not C) = p(A) + p(B) - p(C)
Mike = 1/4 = 3/12
Rob = 1/3 = 4/12
Ben = 1/6 = 2/12
3/12+4/12 - 2/12 = 5/12
the answer is (B)
but my question is...
since the probability of each's winning is
so isn't the probability of either Mike or Rob winning but not Ben and Others = Prob. of Mike + Prob. of Rob, which is 3/12 + 4/12?
and accroding to your explaination, if P (A) and P(B) already does not include P(C), then why is P(C) being substracted from P(A) + P(B)?
am I missing something here?