Probability question?

[LALDAAS]

I made a post in the other gambling forum

I was wondering if any of you number guys are bored and want to take a look and may be throw some numbers around on how bad of an idea this betting stragey is for Roulette.

Yes I know any stragey for Roulette is a bad one, but this is just for fun. /images/graemlins/grin.gif

link (http://forumserver.twoplustwo.com/showflat.php?Cat=&Number=3574237&page=0&view=colla psed&sb=5&o=14&fpart=1)

[Buz]

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What's the risk of ruin?

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If your risk of losing one spin is 7/37, then your risk of losing two in a row is 7/37 of 7/37. In other words, you will lose two in a row 7/37ths of the times you lose one. Consequently, you will only lose 7 in a row 7/37 X 7/37 seven times... or (7/37)^7. I got, like, 8.6 in a million or 1 in 115,000. Any math professors agree?

It looks like it is less risky than say, trying to double up blackjak losses.

[LALDAAS]

Wow I expected worse.

[Justin A]

[ QUOTE ]
Wow I expected worse.

[/ QUOTE ]

It is worse. You'll often stay at the same level for a few spins while you break even by hitting 1 to 18. In other words you don't need to lose 7 consecutive spins, you just need to lose 7 before hitting on 3rd 12.

You are a 12/7 favorite to hit the 3rd 12 before losing on each spin, so you'll lose and move up a level 7/19. The chances of you losing 7 times before winning is 1 in 1085.