Conditional Probability on Cards of the Same Suit
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A normal deck of 52 playing cards is well shuffled and then 4 cards are dealt to Ann and 4 cards ar dealt to Bob. Ann looks at her c that all 4 of them are from the same suit, that suit being hearts. She is interested in the probability that Bob also has 4 cards that belong to a single suit, allowing for her knowledge of the cards she holds.
Please correct my answer if it is incorrect:
$$text{Probability}=P(text{Bob has all hearts} |text{Ann has all hearts})+P(text{Bob has all clubs/spades/diamonds}|text{Ann has all hearts})$$
$$=frac{binom{9}{4}}{binom{48}{4}}+frac{binom{3}{1}timesbinom{13}{4}}{binom{48}{4}}$$
$$=frac{757}{64860}$$
I am aware that this is a conditional probability, but I was unsure how to apply Bayes' Theorem in this scenario.
probability combinations
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up vote
2
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A normal deck of 52 playing cards is well shuffled and then 4 cards are dealt to Ann and 4 cards ar dealt to Bob. Ann looks at her c that all 4 of them are from the same suit, that suit being hearts. She is interested in the probability that Bob also has 4 cards that belong to a single suit, allowing for her knowledge of the cards she holds.
Please correct my answer if it is incorrect:
$$text{Probability}=P(text{Bob has all hearts} |text{Ann has all hearts})+P(text{Bob has all clubs/spades/diamonds}|text{Ann has all hearts})$$
$$=frac{binom{9}{4}}{binom{48}{4}}+frac{binom{3}{1}timesbinom{13}{4}}{binom{48}{4}}$$
$$=frac{757}{64860}$$
I am aware that this is a conditional probability, but I was unsure how to apply Bayes' Theorem in this scenario.
probability combinations
add a comment |
up vote
2
down vote
favorite
up vote
2
down vote
favorite
A normal deck of 52 playing cards is well shuffled and then 4 cards are dealt to Ann and 4 cards ar dealt to Bob. Ann looks at her c that all 4 of them are from the same suit, that suit being hearts. She is interested in the probability that Bob also has 4 cards that belong to a single suit, allowing for her knowledge of the cards she holds.
Please correct my answer if it is incorrect:
$$text{Probability}=P(text{Bob has all hearts} |text{Ann has all hearts})+P(text{Bob has all clubs/spades/diamonds}|text{Ann has all hearts})$$
$$=frac{binom{9}{4}}{binom{48}{4}}+frac{binom{3}{1}timesbinom{13}{4}}{binom{48}{4}}$$
$$=frac{757}{64860}$$
I am aware that this is a conditional probability, but I was unsure how to apply Bayes' Theorem in this scenario.
probability combinations
A normal deck of 52 playing cards is well shuffled and then 4 cards are dealt to Ann and 4 cards ar dealt to Bob. Ann looks at her c that all 4 of them are from the same suit, that suit being hearts. She is interested in the probability that Bob also has 4 cards that belong to a single suit, allowing for her knowledge of the cards she holds.
Please correct my answer if it is incorrect:
$$text{Probability}=P(text{Bob has all hearts} |text{Ann has all hearts})+P(text{Bob has all clubs/spades/diamonds}|text{Ann has all hearts})$$
$$=frac{binom{9}{4}}{binom{48}{4}}+frac{binom{3}{1}timesbinom{13}{4}}{binom{48}{4}}$$
$$=frac{757}{64860}$$
I am aware that this is a conditional probability, but I was unsure how to apply Bayes' Theorem in this scenario.
probability combinations
probability combinations
asked 16 hours ago
An Invisible Carrot
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798
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1 Answer
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$P(A)$ = P(Anne has all hearts) =$$frac{ ^{13}C_4}{^{52}C_4}$$
$P(B)$ = P(Bod has same suite) =$$frac{^{13}C_4cdot ^3C_1+^9C_4}{^{52}C_4}$$
Using:
$$P(Bmid A)=frac{P( A ∩ B)}{P(A)}$$
P(A ∩ B)=$$frac{(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8}$$
You get: $$P(Bmid A)=(frac {(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8 })cdot(frac{^{52}C_4}{^{13}C_4})$$
To obtain $P(B mid A)$, type$P(B mid A)$. Also, check your last line.
– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
|
show 7 more comments
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
$P(A)$ = P(Anne has all hearts) =$$frac{ ^{13}C_4}{^{52}C_4}$$
$P(B)$ = P(Bod has same suite) =$$frac{^{13}C_4cdot ^3C_1+^9C_4}{^{52}C_4}$$
Using:
$$P(Bmid A)=frac{P( A ∩ B)}{P(A)}$$
P(A ∩ B)=$$frac{(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8}$$
You get: $$P(Bmid A)=(frac {(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8 })cdot(frac{^{52}C_4}{^{13}C_4})$$
To obtain $P(B mid A)$, type$P(B mid A)$. Also, check your last line.
– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
|
show 7 more comments
up vote
1
down vote
$P(A)$ = P(Anne has all hearts) =$$frac{ ^{13}C_4}{^{52}C_4}$$
$P(B)$ = P(Bod has same suite) =$$frac{^{13}C_4cdot ^3C_1+^9C_4}{^{52}C_4}$$
Using:
$$P(Bmid A)=frac{P( A ∩ B)}{P(A)}$$
P(A ∩ B)=$$frac{(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8}$$
You get: $$P(Bmid A)=(frac {(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8 })cdot(frac{^{52}C_4}{^{13}C_4})$$
To obtain $P(B mid A)$, type$P(B mid A)$. Also, check your last line.
– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
|
show 7 more comments
up vote
1
down vote
up vote
1
down vote
$P(A)$ = P(Anne has all hearts) =$$frac{ ^{13}C_4}{^{52}C_4}$$
$P(B)$ = P(Bod has same suite) =$$frac{^{13}C_4cdot ^3C_1+^9C_4}{^{52}C_4}$$
Using:
$$P(Bmid A)=frac{P( A ∩ B)}{P(A)}$$
P(A ∩ B)=$$frac{(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8}$$
You get: $$P(Bmid A)=(frac {(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8 })cdot(frac{^{52}C_4}{^{13}C_4})$$
$P(A)$ = P(Anne has all hearts) =$$frac{ ^{13}C_4}{^{52}C_4}$$
$P(B)$ = P(Bod has same suite) =$$frac{^{13}C_4cdot ^3C_1+^9C_4}{^{52}C_4}$$
Using:
$$P(Bmid A)=frac{P( A ∩ B)}{P(A)}$$
P(A ∩ B)=$$frac{(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8}$$
You get: $$P(Bmid A)=(frac {(^{13}C_4 cdot 3+ ^{9}C_4)cdot ^{13}C_4}{^{52}C_8 })cdot(frac{^{52}C_4}{^{13}C_4})$$
edited 11 hours ago
answered 15 hours ago
idea
2,0112923
2,0112923
To obtain $P(B mid A)$, type$P(B mid A)$. Also, check your last line.
– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
|
show 7 more comments
To obtain $P(B mid A)$, type$P(B mid A)$. Also, check your last line.
– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
To obtain $P(B mid A)$, type
$P(B mid A)$. Also, check your last line.– N. F. Taussig
15 hours ago
To obtain $P(B mid A)$, type
$P(B mid A)$. Also, check your last line.– N. F. Taussig
15 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
@N.F.Taussig thanks for that, but whats wrong in last line?
– idea
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
Your probability is greater than $1$.
– N. F. Taussig
14 hours ago
1
1
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
@N.F.Taussig Yeah...$C(52,8)$. And i later added $C(4,1)$ to select a suite-heart; but we dont need to it seems...
– idea
13 hours ago
1
1
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
@N.F.Taussig And Thanks, for taking me through this. Got to learn something new.
– idea
12 hours ago
|
show 7 more comments
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