Question 712820
I have a problem that i cant figure out. 
q. If the odds aginst event E are 2:5, what is the probability of a failure?
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Definitions: odds against E = P(E')/P(E)
And P(E) + P(E') = 1
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Your DATA:
odds against = 2:5 = (2/7)/(5/7
So P(failure) = P(E') = 2/7
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Cheers,
Stan H.