http://www.slate.com/id/2215503/#return Maybe I'm too dimwitted to work there, but I think these questions, or at least the explanations, are wrong. Take the first one, 10 bidding 90, 100 offering 91, what's next price? Anyone who has traded knows it won't be less than 90, but they say the right answer is mid to low 80's. Maybe if you alter the question slightly, otherwise, no way. The coin flip thing, same deal. The theoretical value calculation is straighforward, but only a fool or someone working at AIG would use it to price a ticket to play the game. The explanation ignored to me the salient point--you are playing the game once, not an infinite number of times. Would you risk your entire net worth on a lottery ticket if the odds were favorable?