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Permutations and Combinations
If $nC_{12}=nC_8$ then $n$ is equal to
$\begin{array}{1 1}(A)\;20\\(B)\;12\\(C)\;6\\(D)\;30\end{array} $
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
exemplar
q26
sec-a
easy
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asked
May 16, 2014
by
sreemathi.v
edited
May 9, 2016
by
meena.p
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1 Answer
$n=12+8$
$\;\;\;=20$
Hence (A) is the correct answer.
answered
May 16, 2014
by
sreemathi.v
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