Poker probability The "nCr" function on most scientific calculators can be used to calculate hand frequencies; entering with and , for example, yields formula_2 as above. The royal flush is a case of the straight flush. It can be formed 4 ways (one for each suit), giving it a probability of 0.000154% and odds of 649,739 : 1. When ace-low straights and ace-low straight flushes are not counted, the probabilities of each are reduced: straights and straight flushes each become 9/10 as common as they otherwise would be. The 4 missed straight flushes become flushes and the 1,020 missed straights become no
History of poker early or mid-18th century, and spread throughout the Mississippi River region by 1800. It was played in a variety of forms, with 52 cards, and included both straight poker and stud. 20 card poker was a variant for two players (it is a common English practice to reduce the deck in card games when there are fewer players). The development of poker is linked to the historical movement that also saw the invention of commercial gambling. English actor Joseph Cowell reported that the game was played in New Orleans in 1829, with a deck of 20 cards, and four players