JEE Main 2024 — Permutation Combination Question with Solution
JEE Main 2024 (06 Apr Shift 1)
Question
The number of triangles whose vertices are at the vertices of a regular octagon but none of whose sides is a side of the octagon is
Choose an option
Show full solutionCorrect option: D
Correct answer
D16
Step-by-step explanation
no. of triangles having no side common with a
$\begin{aligned}
& \text { sided polygon }=\frac{{ }^n C_1 \cdot{ }^{n-4} C_2}{3} \\
& =\frac{{ }^8 C_1 \cdot{ }^4 C_2}{3}=16
\end{aligned}$
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This is a previous-year question from JEE Main 2024, covering the Permutation Combination chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.