The odd against event E=3/7, what is P(E)?

Question

The odd against event E=3/7, what is P(E)?

Answer 1

Your question is unanswerable as you state it. The "odds against" an event need to be stated as "x in y" or "x to y". For instance, if a baseball team has a 25% chance of winning a game, then the "odds against" that team are 3 to 1, and the team has a 1 in 4 chance of winning. If you meant that the probability of an event is 3 in 7, (P) is simply the decimal equivalent of the fraction 3/7, or approx. .441.