JEE Mains · Maths · STD 11 - 6. permutation and combination
The number of ways, in which \(5\) girls and \(7\) boys can be seated at a round table so that no two girls sit together, is
- A \(126(5 !)^2\)
- B \(7(360)^2\)
- C \(720\)
- D \(7(720)^2\)
Answer & Solution
Correct Answer
(A) \(126(5 !)^2\)
Step-by-step Solution
Detailed explanation
\(6 ! \times{ }^7 C_5 \times 5 !\) \(\Rightarrow 720 \times 21 \times 120\) \(\Rightarrow 2 \times 360 \times 7 \times 3 \times 120\) \(\Rightarrow 126 \times(5 !)^2\)
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