Anyone here good at math?

Because I'm really not, and I have a theory that needs a solution.

It's about roulette. You have 2500 units, and with a 49% chance of winning each time you can theoretically lose 7 times in a row before you are bankrupt. Each win resets this counter. The max bet is 1500. What's the % chance of hitting a bad streak?

 

Well, you're obviously better than I am at it because I can't even understand the theory.

 

I got a D in it. I do know that it is said - True Virgins Make Dull Company.
However. Aunty was a croupier in her youth, watch the girl for her arm to start to tire, thats how you win at roulette - forget the odds - use your eyes.

 

Sounds logical, but not when it comes to on-line roulette. That monotonous, boring guy talking sounds like he could keep it going all night

 

Oh yay, probabilities.

Did it 5 years ago in high school and have completely forgotten about it.

 

Probably around 7 here.. Forgotten all about it as well. I have access to a math teacher though, maybe I should ask her.

 

You probably should.

I'll send an E-Mail to my maths professor and see what he'll say to it.

Can you define "bad streak", though?

 

That'd be sweet.

Yeah, a bad streak would be to lose 7 times in a row. With the other variables, I'd like to know the statistical % chance of losing 7 times in a row each "cycle".

 

If 'hitting a bad streak' = 'bankrupt'= 'losing 7 times in a row', then ~.9% ( .51^7). .51 being the chance of losing.

edit: In case this is meant to have a practical application, there are rules against systematic betting.

 

.8974% of losing 7 times in a row

 

So almost 1%? That's far lower than I thought it would be... Thanks to both of you for providing me with a solution!

Bonus task: With all the same criterias, what's the % chance if the limit is 6 instead of 7?

 

A monotonous boring guy? Does he spin a wheel? If you are ever in the vacinity of a place where glamorous ladies in high heels take your money, sit and watch for a while - see if the tired girl thing works. As you are watching, the casino will be doing the same thing, to get the girls off before the house pays out too much. Look for the tired ones.

 

It's all online, so that's not an issue, hehe.

 

Request monotonous boring guy be replaced with entertaining eye candy? Isnt the idea to keep you on and keep you entertained and watching?

 

Well, the idea is to make money, if possible.

 

If your chance of losing is 0.51 and you want to know the probability of losing x times, calculate 0.51^x.

 

If there were a legitimate way to reliably make money at the house's expense, there would be no casinos online or otherwise.

 

Systematic betting can be used to overcome the odds and win money on a variety of games, roulette is probably the easiest example. Bet the minimum on black. If you lose bet double the total lost so far. Repeat until winning, then start over.

Bet 5 - lose
Bet 10 - lose
bet 30 - lose
bet 90 - lose
bet 270 - lose
bet 1620 - win
start over.

Basically, you always 'win' unless you lose up to the table maximum.

The problem is this is disallowed at every casino I've ever hear of. If I'm not mistaken in Vegas they're allowed to throw you out, in Atlantic City they can't throw you out but they can order you to 'flat bet'(bet the same amount ever time) or leave. I would assume an online casino would have safeguards in place to prevent this sort of thing.

 

Most casinos online do not have apparent safeguards, but without having the source code for the program it's pretty much impossible to find out the actual odds. Where it should be around 49%, it could in fact be a whole different number.

 

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