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-   -   fictional roulette tactics (http://mymathforum.com/probability-statistics/327338-fictional-roulette-tactics.html)

 Vike February 10th, 2016 04:00 AM

fictional roulette tactics

So there's a roulette in this game I'm playing for ingame currency only. There is no way to get currency in the first place by buying with real life money so don't you worry about that. Basically it's just a harmless minigame.

So here's the roulette, very simple. You have 40% chance of winning and you can bet whatever you want and how many times you like. Winning gives you 100% of bet back.

So here's the question: what would be the best tactic in assuring the most winnings in a safe manner. Your first thought might be that it is impossible, but I think it's not. The bread and butter of assuring this is that you can bet so that you gain back all that you might have lost at the last bet.
Say I bet 10 and lose. The next bet I set to 20 so that if I win I gain what I lost and then some. If I lose again I bet enough to still gain 10 after the first two losses, so 40. I can continue this until I have won back everything I lost and then some.

When I win, I go back to betting 10 and continue in this manner. As you can understand your initial bet has to be a small fraction of your whole sum of currency. But the idea is to gain slowly, but surely. This way I can go in pluss, while still having less than 50% winrate. Essentially I'm making sure that the bets I win are bigger than the ones I lose.

This went well the first day and I almost doubled my money. But then I got in a loss stream and almost lost it all.

Let's say I have 1000 of the fictional currency now. So what do you think would be the best way to go about this? Is there even a mathematically correct way to play this?

 Country Boy February 10th, 2016 05:08 AM

First, you say "Winning gives you 100% of bet back". Do you mean you get your bet back plus 100% of your bet? If all you get back is 100% of your bet, you will never gain, even if you always win!

The 'method' you mention is often called "the gambler's ruin". It will work as long as you start with an infinite amount of money- which, of course, no one does! If your chance of winning on any one turn is 40% and each turn is independent of the previous turn, there is NO way of guaranteeing you will win.

 Vike February 10th, 2016 05:19 AM

Earnings

By 100% I mean you get everything back doubled. But you already knew that :p

 Hoempa February 10th, 2016 05:59 AM

Quote:
 Originally Posted by Vike Is there even a mathematically correct way to play this?
Don't play at all unless you don't care about losing.

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