Wikipedia:Reference desk/Archives/Mathematics/2013 July 27

= July 27 =

Probability in European Roulette
If you make the same even money or 2 to 1 bet 30 times when playing European roulette, how many bets should you win and how many bets should you lose? — Preceding unsigned comment added by 174.65.3.227 (talk) 00:57, 27 July 2013 (UTC)
 * Given a literal reading of your question, a 18/37 bet any number of times has an expected value of 48.6%. I suspect this is a homework question and I also suspect that's not exactly the question being asked... but it's the question asked here. Shadowjams (talk) 05:17, 27 July 2013 (UTC)

No, it isn't a homework question. I'm just wondering how many times I can expect to win and how many times I can expect to lose if I bet on the same even money or 2 to 1 bet 30 times in a row. And will the answer that is correct on paper be entirely different during actual gameplay? — Preceding unsigned comment added by 174.65.3.227 (talk) 01:29, 28 July 2013 (UTC)


 * Roulette doesn't have an exact 50% chance of winning, but taking this figure, in 30 plays you expect to win 15 and lose 15 (on the basis of expectation). Yes, it will be entirely different in actual gameplay, as if you play enough "30 games", eventually every possibility from (0 wins, 30 losses) to (30 wins, 0 losses) will occur. The binomial distribution will give the relative frequency of the 31 possible outcomes for each set of 30 plays.→86.140.134.100 (talk) 13:11, 28 July 2013 (UTC)