Holdem Poker Online is a member of the THP Texas Holdem Online Poker strategy network.



How do you calculate the probability of a hand?



Posted Fri Mar 11, 2005 10:55 pm GMT by FirebirdGM
I was thinking about this today, and realized I have no idea.

Take for example, I want the probability of me getting a royal flush on any given hand. Assuming both of my pocket cards are part of the Royal Flush, what is the chances, and how do you calculate this?

I was thinking something along the lines of this, but I'm probably very, very far off.

Card 1: 20/52 10-A of any suit
*
Card 2: 4/52 One of the others of the drawn suit
*
Card 3: 3/52
*
Card 4: 2/51
*
Card 5: 1/51

Would that be the odds of getting a royal flush With your pockets and the flop? How would you add the Turn/River? Assuming I'm anywhere near the right way of calculation


$200K Gtd Sunday Qualifier 1 Seat Gtd at PartyPokerStarts in 8 minutes
WSOP Sub Qualifier Speed Rebuy at PartyPokerStarts in 8 minutes
Regular at PartyPokerStarts in 18 minutes
Summer Million MEGA Friday Satellite Qualifier Speed Rebuy at PartyPokerStarts in 23 minutes
BankrollMob April $25 Freeroll at PartyPokerStarts in 28 minutes
New Player Lucky Dollar at PartyPokerStarts in 33 minutes
WPT National Madrid Sub Qualifier Speed at PartyPokerStarts in 33 minutes
Players Club $500 at PartyPokerStarts in 38 minutes
25 PP Summer Million Special Qualifier Speed at PartyPokerStarts in 38 minutes
Summer Million Sub Qualifier Speed Rebuy at PartyPokerStarts in 38 minutes
Show all upcoming online poker freerolls

Did you know that participating in a poker forum can help you improve your own game? Be it by sharing experiences or simply asking for help, participation in a forum helps you focus and keep 'on topic' which will help you improve your game. You can learn from other players feedback and from their experiences. Why the THP poker forums? We offer one of the best managed texas holdem poker forums available, and the community within is far more friendly than those typicaly found on other sites.

We've made a 'lurkers edition' of the poker forum available here on Holdem Poker Online, but we encourage all visitors to
register and join in on the conversations on TexasHoldem-Poker.com


Posted Fri Mar 11, 2005 11:38 pm GMT by galderon
FirebirdGM wrote:

Card 1: 20/52 10-A of any suit
*
Card 2: 4/52 One of the others of the drawn suit
*
Card 3: 3/52
*
Card 4: 2/51
*
Card 5: 1/51

Would that be the odds of getting a royal flush With your pockets and the flop?


That's my thinking as well (that is to say, I agree with you, but I may be wrong)...though you need to keep removing cards from the total deck...so it's 20/52 * 4/51 * 3/50 * 2/49 * 1/48...approximately 0.00015%. It's actually happened to me online...play money though. Smile



Posted Sat Mar 12, 2005 12:24 am GMT by galderon
I think the chance of a royal on the flop or turn is the above chance, times six...meaning that there's one card that you don't care about that occurs in one of the six places:

20/52 * 4/51 * 3/50 * 2/49 * 1/48 * 6 = 0.0009%

The chance that a royal occurs sometime during the community is the above chance of it occuring on the flop, times 21...the two cards you don't care about can be located in 21 different configurations:

20/52 * 4/51 * 3/50 * 2/49 * 1/48 * 21 = 0.0032%

Hmmm...that reasoning makes sense to me, but I can't think of a way to explain it. It might not even be correct! Confused






Latest poker forum activity