JEE Main 2021 · MathsMultiple choiceSingle correctEasyCalculation

JEE Main 17 March 2021, Shift 2, Maths Q72

Question 72 of 90 in this shift, Maths question 12 of 30, Section A.

If the sides AB, BC and CA of a triangle ABC have 3, 5 and 6 interior points respectively, then the total number of triangles that can be constructed using these points as vertices, is equal to :

(1) $360$
(2) $364$
(3) $333$ Official answer
(4) $240$

Official answer

Option 3

NTA final key.

Chapter: Permutations and Combinations
Topic: Permutations and Combinations
Idea tested: Triangles from Points with Collinearity

Same idea in other shifts

Asked 4× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.