COMEDK · Maths · 4. Permutation Combination
A polygon of \(n\) sides has 105 diagonals, then \(n\) is equal to
- A 20
- B 21
- C 15
- D -14
Answer & Solution
Correct Answer
(C) 15
Step-by-step Solution
Detailed explanation
\(\because\) The total number of lines joining any two points of the polygon is given by \({ }^n C_2\) So, \({ }^n C_2=105\)…
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