suppose something that has only a one-in-five chance (20 percent) of succeeding will return ten times (e.g., $1,000) the amount that it will cost you if it fails ($100). Its expected value is positive ($120), so it’s probably a smart decision, even though the odds are against you, as long as you can also cover the loss. Play these probabilities over and over again and they will surely give you winning results over time.
