A “mathematically fair bet” is one in which the amount won will on average equal the amount bet, for example when a gambler bets, say, $100 for a 10 percent chance to win $1,000 ($100 = .10 x $1,000). Assuming diminishing marginal utility of dollars, explain why this is not a fair bet in terms of utility. Why is it even a less fair bet when the “house” takes a cut of each dollar bet?  So is gambling irrational?