WBJEE · Maths · Permutation Combination
There are \(n\) white and \(n\) black balls marked \(1,2,3, \ldots . n\). The number of ways in which we can arrange these balls in a row so that neighbouring balls are of different colours is
- A \((n !)^2\)
- B (2n)!
- C \(2(n !)^2\)
- D \(\frac{(2 n) !}{(n !)^2}\)
Answer & Solution
Correct Answer
(C) \(2(n !)^2\)
Step-by-step Solution
Detailed explanation
BW BW ..... \(=n ! \times n !\) or WB WB ..... \(=2(n !)^2\)
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