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There are $52$ cards in a deck is distributed equally to $4$ people. What is the probability for one of 4 people to get $13$ cards such that none of them have the same value?

Example:

  • {2♥, 3♥, 4♥, 5♥, 6♥, 7♥, 8♥, 9♥, 10♥, J♥, Q♥, K♥, Ace♥} is correct
  • {3♠, 3♥, 4♥, 5♥, 6♥, 7♥, 8♥, 9♥, 10♥, J♥, Q♥, K♥, Ace♥} is incorrect

Note: my teacher said result $\frac{4^{13}}{^{52}C_{13}} \approx 0.0001057$ is incorrect and the order of 13 cards on player's hand does not matter.

My programming experiment:

I know a bit about Python programming, so I did a test, my test specific was:

  • A deck is distributed equally to $4$ people
  • Then I check if any player satisfies 13 cards and none of them have the same number $\Rightarrow$ this is a successful experiment and if none of 4 people matches the condition so this is an unsuccessful experiment.

I do this test 100 000 times, add up all the successful experiments and divide it by 100000, the probability always falls between 0.0003 and 0.0005

  • What else have you tried? – KingLogic Dec 08 '20 at 03:29
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    The result in note section is my answer, but my teacher said "your answer is incorrect" – Claire Duong Dec 08 '20 at 03:30
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    Does the question ask for the probability that a particular player does not get two cards of the same value, or does it ask for the probability that no player gets two cards of the same value? – Brian M. Scott Dec 08 '20 at 03:31
  • @BrianM.Scott I updated my question, thanks for viewing my post. – Claire Duong Dec 08 '20 at 03:36
  • @ClaireDuong: Your edit doesn't seem to clarify Brian's question: does the question ask for the probability that a particular person's hand doesn't get two cards of same value or that none of the 4 people get such a hand. I believe it's the latter case because the former case has the answer you gave, which your teacher marked as incorrect. – Prasun Biswas Dec 08 '20 at 03:46
  • @PrasunBiswas probability for any person in 4 people to get a set of 13 cards that none of them have the same value each other – Claire Duong Dec 08 '20 at 03:53
  • @ClaireDuong: yes, that's the latter case which is best addressed in Brian's answer. – Prasun Biswas Dec 08 '20 at 03:55
  • The phrase “any person” is ambiguous. Does it mean “exactly one of the four players”, does it mean “one or more of the four players” or does it mean “each one of the four players” ? – gandalf61 Dec 08 '20 at 04:07
  • I edited my answer to include exact calculation. – herb steinberg Dec 10 '20 at 22:32

5 Answers5

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You need to count the number of ways in which each person can receive one card of each denomination. Each denomination can be distributed to the $4$ players in $4!$ different ways, so there are $4!^{13}$ different deals that give each player one card of each denomination. There are

$$\binom{52}{13}\binom{39}{13}\binom{26}{13}\binom{13}{13}=\binom{52}{13,13,13,13}=\frac{52!}{13!^4}$$

possible deals, so the desired probability is

$$\frac{4!^{13}}{\frac{52!}{13!^4}}=\frac{4!^413!^4}{52!}\,,$$

which is a bit more than $6\times 10^{-24}$.

Added: This is the probability that each player receives one card of each denomination. Subsequent edits make it unlikely that this is the intended interpretation of the question. If what is desired is the probability that at least one player receives a card of each denomination, or that exactly one player does so, the calculation is significantly messier.

Brian M. Scott
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  • This looks like all four players have the desired result! – herb steinberg Dec 08 '20 at 04:23
  • @herbsteinberg: It is; given that the OP’s original answer was incorrect, that seemed the likeliest interpretation. However, the very recent edit makes that seem rather doubtful, and I’m not at all sure what was intended. At least one player gets such a hand? Exactly one player gets such a hand? Either of those gets a bit messy. – Brian M. Scott Dec 08 '20 at 04:26
  • I tried to answer the question and got the "incorrect" answer, so I added the comment which is what you noted. However, since the original answer is so small, a good approximation for at least one player getting a "good" hand would be four times as much. The probability of two players getting such hands is minuscule. Note that your answer doesn't take into account the fact that if three players get such hands, then automatically the fourth player must also. – herb steinberg Dec 08 '20 at 04:42
  • @herbsteinberg: The fact that if three players get such hands, the fourth must also get one is irrelevant to the approach that I took. I simply calculated the number of deals in which all four players do get such hands and divided by the number of possible deals (where deal refers to the distribution of cards amongst the players, not to the specific order in which they were distributed). – Brian M. Scott Dec 08 '20 at 04:50
  • I edited my answer to include exact calculation. – herb steinberg Dec 10 '20 at 22:32
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If the question asks for the probability that a particular person's hand doesn't have two cards of same value, then:

Out of the 13 cards in your hand, the first can be any of the 52 cards.

For the second one, it can be any of 48 cards (excluding the first card and 3 other cards of other suits with the same value)

For the third one, it can be any of 44 cards (excluding the first two cards and the cards with same value but different suits)

Continuing similarly, there are $52\times 48\times\dots\times 8\times 4=4^{13}\times 13!$ favorable configurations out of the $52!$ configurations. This results in the answer you gave, ie, $\dfrac{4^{13}\times 13!}{52!}=\dfrac{4^{13}}{\binom{52}{13}}$, so I think your teacher referred to the latter case in the problem.


If the probability is that no person gets two cards of same value, then count configurations where each person gets a hand with all value cards but different suits, so $4!^{13}$ configurations out of a total of $\binom{52}{13}\binom{39}{13}\binom{26}{13}\binom{13}{13}$ configurations (total number of possible deals) because for each value card, the suits in the 4 player hands can be permuted in $4!$ ways for each of the 13 valued cards.

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Calculation based on first card is free. Get probability all remaining cards have to be different. Second card is $\frac{48}{51}$ third card is $\frac{44}{50}$ summary is $\frac{12!\times 4^{12}\times 39!}{51!}=0.000105681$

This is the probability for one particular player getting it right. Since there are four players the question seems to be at least one gets the desired result. That is approximately $4$ times as much, ignoring dependency of the hands.

............ exact calculation. Let $P_1$ be the result of the above calculation. $P_2= \frac{12!\times3^{12}\times26!}{38!}=0.0001962866$ and $P_3=\frac{12!\times2^{12}\times13!}{25!}= 0.0007876469$

The probability at least one good hand $=P_1$, the probability of at least two good hands is $Q=P_1P_2$, and the probability of all four hands are good is $R=P_1P_2P_3$.

One or more good hands occurs four times each includes two or more three times, while each two or more includes one all. Adding it all up and removing duplicates the final probability is $4P_1-6Q+3R$.

  • I don't understand formula $4P_1 - 6Q + 3R$ very well, can you explain it better, thanks – Claire Duong Dec 11 '20 at 11:38
  • Mutually exclusive events of interest are $E_1$ exactly one good hand, $E_2$ exactly two good hands, and $A$ all good hands. The direct calculations however are for events $A_1$ one or more good hands and $A_2$ two or more good hands. $A_1$ is the union of disjoint parts $E_1+3E_2+A$ while $A_2$ consists of $E_2+A$. At least one good hand among four dealt consist of (disjoint) events $4E_1+6E_2+A$.which requires $4A_1-6A_2+3A$ with the probabilities $4P_1-6Q+3R$. I hope this clarifies. – herb steinberg Dec 11 '20 at 18:05
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You should get $13$ different values. First card has $52$ choices, second has $48$ choices, etc down to $4$. So multiply all multiples of $4$ from $4$ to $52$, and divide by the total, which is ${52} \choose 13$.

When you simplify you should get $\frac{4^{13}\times 13!}{52 \choose 13}$

KingLogic
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Imagine arranging the cards in 13 rows and 4 columns. The first row contains all four aces, the second row contains all four kings, the third row contains all four queens, etc. Assign the first column of cards to person #1, the second column of card to person #2, the third column of cards to person #3, and the fourth column of card to Person #4. Since are $4!$ ways to arrange the cards in each row, the total number of such arrangements is $(4!)^{13}$ making the desired probability $\frac{(4!)^{13}}{{52 \choose 13}{39 \choose 13}{26 \choose 13}{13 \choose 13}}$

Matthew H.
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