# roulette odds

Closet Gooner

Joined: 24 Sep 2006
Posts: 4483
Location: nottinghamshire

Posted: Tue Jun 25, 2013 4:10 pm
in a single session of playing until either it lands black seven times in a row or lands on zero twice in a row.
what is the probability of which will happen first?
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Straight Flush

Joined: 30 Jun 2007
Posts: 2674
Location: East Yorks

Posted: Tue Jun 25, 2013 4:37 pm
Surely 7 x blacks ftw?
2 x zero = 37x37 innit?

Oh wait that's all wrong...... It depends how many spins of the wheel there are. Zero is only 36-1 once a zero has already spun
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Straight Flush

Joined: 30 Jun 2007
Posts: 2674
Location: East Yorks

Posted: Tue Jun 25, 2013 4:39 pm
Oh forget the above.... it's utter bollox as per norm
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Checkov
Royal Flush

Joined: 12 Sep 2003
Posts: 10111

Posted: Tue Jun 25, 2013 5:20 pm
(18/37)^7 > (1/37)^2
(18/37)^7 / (1/37)^2 = 8.8x more likely to see 7 reds in a row

Or if you start after seeing the first one.
1/37 > (18/37)^6
1/37)^2 / (18/37)^6 = 2
stowjon
Royal Flush

Joined: 26 Oct 2008
Posts: 9071

Posted: Tue Jun 25, 2013 5:23 pm
same number twice in a row is 1/1444

same colour 8 times in a row is 169/1 (based on a dbl zero wheel)
Straight Flush

Joined: 30 Jun 2007
Posts: 2674
Location: East Yorks

Posted: Tue Jun 25, 2013 6:56 pm
Gawd I was right 1st time. Please block me from this thread....

Why OP?
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