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Saborion
01-06-2004, 10:46 PM
The chance of getting dealt a specific pocket pair is 1:221 right? What`s the probability that you`re dealt the same pair again (neglecting suits)? This is something I`ve always had problem understanding.

If you flip a coin, you have a 50/50 chance of getting tails, it really doesn`t matter what the outcome was of the previous flip was, does it? Even so, the probability of getting two tails in a row is .5*.5 = .25? So, it I do get tails on the first attempt, is it only 25 % chance that I get tails again, or is it 50 %?

Henke
01-06-2004, 11:38 PM
[ QUOTE ]

If you flip a coin, you have a 50/50 chance of getting tails, it really doesn`t matter what the outcome was of the previous flip was, does it? Even so, the probability of getting two tails in a row is .5*.5 = .25? So, it I do get tails on the first attempt, is it only 25 % chance that I get tails again, or is it 50 %?

[/ QUOTE ]

You have to be very strict when defining a mathematical problem. If you ask for the probability of getting two tails on two consecutive flips, the probability is 25%, but if you ask the probability of getting a tail when you know you've just had a tail, it's 50%, because the coin has no "memory".

So the probability of getting dealt AA two consecutive deals is mathematicaly not the same as the probability of getting AA the next deal, when you had AA on this one. (The cards have no memory neither.)

Saborion
01-07-2004, 06:07 AM
Sort of interesting.
I mean, say I`m sitting in a tourny where a guy just had AA and busted another player. Now on the next hand I`m dealt KK and is up against that same player. Is the probability that he has AA again (1/221)*(1/221) or is it 1/221? Both answers are true, in their own ways right? Although in this case I`d say it`s 1/221 due to the no memory. Or am I wrong then? /images/graemlins/smile.gif

mojito
01-13-2004, 03:33 AM
the coin problem reminds me of a continual argument with one of my friends about the black/red bet on a roulette...
he sees 9 previous blacks on a roulette display and he tells me that it is more probable now that a red will hit... and i can't stop repeating to him that the probability is always 50%, regardless of the history...

just checking if u guys agree with me.

Henke
01-13-2004, 04:05 AM
Try asking your friend if he agrees to take a bet with a 3:2 proposition, so that you get \$3 from him if a 10:th red comes, and he get \$2 from you if a black comes. That should make you some money!

flopdanutz
01-13-2004, 04:55 AM
when u hold KK the prob of a specific player holding AA is
(4/50) * (3/49) or 0.489% slightly higher than 1/221
because you are holding two non aces which increases the chance that your opponent has an ace.

if u did not peek at your cards (thus not knowing the cards your opponent cannot have) then the probability of your opponent having AA would be 1/221

OldLearner
01-13-2004, 01:50 PM
What if the Question were:

At this specific moment, what are the odds that I will dealt AA in the next hand and the hand after?