JEE Mains · Maths · STD 11 - 6. permutation and combination
Some couples participated in a mixed doubles badminton tournament. If the number of matches played, so that no couple played in a match, is \(840\), then the total numbers of persons, who participated in the tournament, is \(........\).
- A \(14\)
- B \(12\)
- C \(10\)
- D \(16\)
Answer & Solution
Correct Answer
(D) \(16\)
Step-by-step Solution
Detailed explanation
\({ }^n C_2 \times{ }^{n-2} C_2 \times 2=840\) \(\Rightarrow n=8\) Therefore total persons \(=16\)
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