JEE Main · Maths · Permutations and Combinations
Number of Triangles from Points
JEE Main asked Number of Triangles from Points 3 times in 3 of the 108 shifts Lumi analysed, in 2021, 2025 and 2026. It belongs to Permutations and Combinations (Maths). The longest wait between two years asking it was 4 years.
Updated 2026-10-24
- Times asked
- 3
- in 3 shifts
- Years
- 3 of 8
- First asked
- 2021
- last in 2026
- Pattern
- Frequent
- across the analysed shifts
Questions on this idea a shift, by year
2017–2026. Asked in 2021, 2025 and 2026. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift of 25 Maths questions.
Raw count: 2017: 0 in 1 shift · 2020: 0 in 12 shifts · 2021: 1 in 24 shifts · 2022: 0 in 24 shifts · 2023: 0 in 12 shifts · 2024: 0 in 18 shifts · 2025: 1 in 8 shifts · 2026: 1 in 9 shifts.
Shift by shift
Each square is one analysed shift, in date order. Open a filled one for that paper.
How JEE Main framed it
Single correct is the usual form. Skill tested: multi-step.
- Count triangles from polygon vertices
- Count polygons from vertices then ellipse eccentricity
Difficulty
Every question was multiple choice.
Every question
All 3 questions
From the official JEE Main shift papers, newest first. Open one for the full question, the options and the official answer.
- 2 Apr 2026, Shift 2 · Q7Let denote the total number of triangles formed by joining the vertices of an -side regular polygon. If ,…EasySingle correct
- 7 Apr 2025, Shift 2 · Q8Let be the number of all triangles that can be formed by joining the vertices of a regular polygon of sides and be the…MediumSingle correct
- 16 Mar 2021, Shift 2 · Q73Consider a rectangle ABCD having 5, 7, 6, 9 points in the interior of the line segments AB, CD, BC, DA respectively. Let be the…MediumSingle correct
Shifts: 16 Mar 2021, Shift 2, 7 Apr 2025, Shift 2, 2 Apr 2026, Shift 2.
Same topic
Other ideas in Permutations and Combinations
Permutations and Combinations has 33 ideas JEE Main has asked; 20 of them came up in more than one question. The 12 most asked are below.
- Combinations of Distinct Objects16× · 2026
- Fundamental Counting Principle13× · 2025
- Distribution of Identical Objects11× · 2026
- Permutations with Repetition11× · 2023
- Permutations of Distinct Objects10× · 2023
- Lexicographic Rank of a Word8× · 2024
- Number of Injective Functions7× · 2026
- Number of Surjective (Onto) Functions6× · 2026
- The Block/Tie Method6× · 2026
- Total Number of Functions5× · 2024
- Triangles from Points with Collinearity4× · 2025
- Selection of One or More Objects4× · 2024