WBJEE · Maths · Permutation Combination
The number of selection of \(n\) objects from \(2 n\) objects of which \(n\) are identical and the rest are different, is
- A \(2^{n}\)
- B \(2^{n-1}\)
- C \(2^{n}-1\)
- D \(2^{n-1}+1\)
Answer & Solution
Correct Answer
(A) \(2^{n}\)
Step-by-step Solution
Detailed explanation
Number of ways of selection of \(n\) objects from \(2 n\) objects, where as \(n\) objects are identical in out of \(2 n\) objects. \(n\) identical and no different object \(=1\) ways \[ ={ }^{n} C_{0} \] \(n-1\) identical and 1 different object \(=1 \times{ }^{n} C_{1}\) \(n-2\)…
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