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CBSE XI
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Permutations and Combinations
True-or-False:If some or all of n objects are taken at a time,the number of combinations is $2^n-1$
$\begin{array}{1 1}(A)\;\text{True}\\(B)\;\text{False}\end{array} $
cbse
math
class11
ch7
permutations-and-combinations
exercise7-3
true-or-false
exemplar
q55
sec-a
easy
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May 16, 2014
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sreemathi.v
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1 Answer
No of objects =n
No of combinations =$2^n-1$
Hence it is true.
answered
May 16, 2014
by
sreemathi.v
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