Number of ways to pick an equal number of elements from two sets?
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There are two groups such that one group contains $m$ elements and another group contains $n$ elements. We have to find number of ways to pick same number of elements from both the groups.
My approach is
$1+dbinom m1.dbinom n1+dbinom m2 . dbinom n2 +.... $upto $dbinom mm$ or $dbinom nn$ whatever is smaller.
Is there any faster way to do the same?
Example:
$3$ and $2$
$1+dbinom 31.dbinom 21+dbinom 32 . dbinom 22=10$ ways
combinatorics permutations
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There are two groups such that one group contains $m$ elements and another group contains $n$ elements. We have to find number of ways to pick same number of elements from both the groups.
My approach is
$1+dbinom m1.dbinom n1+dbinom m2 . dbinom n2 +.... $upto $dbinom mm$ or $dbinom nn$ whatever is smaller.
Is there any faster way to do the same?
Example:
$3$ and $2$
$1+dbinom 31.dbinom 21+dbinom 32 . dbinom 22=10$ ways
combinatorics permutations
New contributor
add a comment |
up vote
2
down vote
favorite
up vote
2
down vote
favorite
There are two groups such that one group contains $m$ elements and another group contains $n$ elements. We have to find number of ways to pick same number of elements from both the groups.
My approach is
$1+dbinom m1.dbinom n1+dbinom m2 . dbinom n2 +.... $upto $dbinom mm$ or $dbinom nn$ whatever is smaller.
Is there any faster way to do the same?
Example:
$3$ and $2$
$1+dbinom 31.dbinom 21+dbinom 32 . dbinom 22=10$ ways
combinatorics permutations
New contributor
There are two groups such that one group contains $m$ elements and another group contains $n$ elements. We have to find number of ways to pick same number of elements from both the groups.
My approach is
$1+dbinom m1.dbinom n1+dbinom m2 . dbinom n2 +.... $upto $dbinom mm$ or $dbinom nn$ whatever is smaller.
Is there any faster way to do the same?
Example:
$3$ and $2$
$1+dbinom 31.dbinom 21+dbinom 32 . dbinom 22=10$ ways
combinatorics permutations
combinatorics permutations
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New contributor
edited yesterday
SmarthBansal
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36412
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asked yesterday
Sagar Sharma
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Sagar Sharma is a new contributor. Be nice, and check out our Code of Conduct.
Sagar Sharma is a new contributor. Be nice, and check out our Code of Conduct.
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