combinations

carebear

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Aug 30, 2010
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From a deck of 52 cards, how many ways can 5 cards be dealt to get "4 of a kind"?

Why isn't it C(52,4) x C(48,1)?


Does C(52,4) reduce to C(13,1)?
 
\(\displaystyle \binom{4}{1}\cdot\binom{12}{1}\cdot\binom{13}{1}\)

See why?.

Does C(52,4) reduce to C(13,1)?

No. It is not a fraction. C(13,1)=13. C(52,4)=270725

Quite a difference.
 
Hello, carebear!

From a deck of 52 cards, how many ways can 5 cards be dealt to get "4 of a kind"?

Why isn't it C(52,4) x C(48,1)? . . . . Because it's wrong

Think about what you have written . . .

\(\displaystyle C(52,4)\) is the number of ways ANY 4 cards can be dealt from the deck.

\(\displaystyle C(48,1)\) is the number of ways 1 card can be dealt from the remaining 48 cards.

No mention is made of a "4 of a kind".

 
Can you please further explain C(4,1) x C(12,1) x C(13, 1) with words and not numbers? I am having trouble understanding.

Does the first part mean.....choose one of the 4 suits.....or does it relate to the 4 of a kind?

Sorry....I am soooo confused on permutations and combinations, etc..
 
C(13,1) means you are choosing 1 from the 13 values for the '4 of a kind'. You can have 4 Aces, 4 Deuces, 4 Treys, 4 Fours, etc.

C(12,1) is choosing 1 from the other 12 for the fifth card.

C(4,1) is choosing 1 from the four suits.
 
Thank you very much.....now if the question says: How many 5 card hands contain: 3 of one kind and 2 of another...is this correct?

C(13,1) - choose a jack for example from 13 possible cards in a suit
C(4,3) - there are 4 jacks to choose from and I need to pick 3
C(12,1) - choose a seven for example, but because I have already selected a jack, i only have 12 cards remaining in that suit
C(4,2) - there are 4 sevens to choose from and I need to pick 2

I would then multiply this together.....do my explanations sound correct?
 
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