If you are dealt five cards and only five cards from a

Question

If you are dealt five cards and only five cards from a single, normal deck of cards, what is the probability of receiving a straight flush? A straight flush is 5 cards in numerical sequence, all of which are the same suit. (example: 2,3,4,5,6 of hearts).

ethan_casta · Answer

Answer: A,2,3,4,5,6,7,8,9,10,j,q,k,a............ ace counts as 1 or 11

Each suit has 13 cards. There are 10 ways you can choose 5 consecutive cards for each suit. see above for yourself. 

ex. a,2,3,4,5;;;;;2,3,4,5,6;;;;;;;etc

so 10 for each suit * 4 suits = 40 possible hands that satisfy the criteria.

Total possible hands: 52C5

Probability = 40/52C5

andrehaui · Answer

FOR A PPOKER PLEAYR THATS EASY....40/52

BUT WHAT'D BE THE FORMULA FOR FINDING 10 CASES FOR EACH 13 CARDS WITH 1 REPETITION?

Caas · Answer

Are you sure that there are only 10 ways of chosing 5 consecutive cards for each suit?
There are 10 ways of chosing them one after one. Like this: first 2, then 3, then 4, then 5 and the last will be 6. But we can also chose them in another order: first we will take 6, then 2, then 4 etc....
Does order matter here? Should we also take into account other possibilities?

BTW there are not 40, but 36 possible flash streets.
(13-5+1)*4

defenestrate · Answer

no there are 10 ways
A-5
2-6
3-7
4-8
5-9
6-10
7-J
8-Q
9-K
10-A

gmatiscoming · Answer

would a problem like this appear on the GMAT... I mean it seems awfully biased towards westerners, no? I mean, maybe a deck of cards are different in India or China I dunno...

LM · Answer

Deck of cards is SAME everywhere, anywhere, whether it's India or China, perhaps you never had the interest in the deck of cards, buy one set and know it!! the problem is not so tough that it can't be in GMAT!

gmatiscoming · Answer

LM,

I am glad you have traveled the world over and are omniscient of all things to know that with no uncertainty decks of cards are identical everywhere. My post was not about the level of difficulty, but was a comment on what I perceived as the blatant "American-ness" of the question. My undergrad major is in marketing (research) with a minor in sociology; so some of the basics that I have learned were: 1) the way you ask a question affects the answer and 2)it is important to look beyond one's self reference criterion. 

Finally, the GMAT is a test that is given worldwide (i believe) in the same format, which is why I was concerned if this was an OFFICIAL question. Considering that the GMAT at its core is really just a big statistical monster (hell, the AWA is really just two looong open ended response questions - they are even "coded" by two different entities like formal research procedures would dictate) to be truly valid you need to ensure 3) construct equivalence to make sure you are measuring the same phenomena correctly. In a marketing setting, at its simplest this means you don't give a survey to someone in India asking them to think in miles when they use kilometers, etc. You'd need conversion of units... which brings me to my point: if this were an official question, they'd need to convert the units and answer based on the country, or tell the respondent there are 52 cards and 4 suits.

I realize this kind of abstract thinking is of little use on the GMAT, but it is valuable in the real world when math tricks and formulae are of little use.
Just to prove my point, I checked out Wikipedia:

The cards of Hungary, Austria, Slovenia, the Czech Republic, Croatia, Slovakia, western Romania and southern Tyrol use the same colors (hearts, bells, leaves and acorns) as the cards of Southern and Eastern Germany. They usually have a deck of 32 or 36 cards. The numbering includes VII, VIII, IX, X, Under, Over, King and Ace. Some variations with 36 cards have also the number VI. The VI in bells also has the function like a joker in some games and it's named Welli or Weli.

Switzerland

In the German-speaking part of Switzerland, the prevalent deck consists of 36 playing cards with the following suits: roses, bells, acorns and shields. The ranks of the alternate deck, from low to high, are: 6, 7, 8, 9, banner (10), "under", "over", king and ace. In the French part of the country, the most used deck is the French deck.

Italian playing cards most commonly consist of a deck of 40 cards (4 suits going 1 to 7 plus 3 face cards), and are used for playing Italian regional games such as Scopa or Briscola. 52 (or more rarely 36) card sets are also found in the north. Since these cards first appeared in the late 14th century when each region in Italy was a separately ruled province, there is no official Italian pattern. There are sixteen official regional patterns in use in different parts of the country (about one per province). These sixteen patterns are split amongst four regions:

Caas · Answer

Yes, it's true. In Russia we use deck of cards with only 36 cards. :!:

BUT when you see a problem like the one above in GMAT remember that when GMAC talk about deck of cards they mean 52 cards. Always they mean: 52 cards 4 suits 13 cards in each suite :wink:

LM · Answer

I haven't travelled world over, but my intention wasn't to waste your precious time in wikipedia, just searching for the deck of cards. As replied in the next post, please remember only that and you shall be in 700 club.

All the best.

If you are dealt five cards and only five cards from a

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