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Saturday, 31 October

JEE Main 2024 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 4 April 2024, Shift 1, Maths Q21

Question 21 of 90 in this shift, Maths question 21 of 30, Section B.

In a survey of 220 students of a higher secondary school, it was found that at least 125 and at most 130 students studied Mathematics; at least 85 and at most 95 studied Physics; at least 75 and at most 90 studied Chemistry; 30 studied both Physics and Chemistry; 50 studied both Chemistry and Mathematics; 40 studied both Mathematics and Physics and 10 studied none of these subjects. Let m and n respectively be the least and the most number of students who studied all the three subjects. Then m+nm+n is equal to ________.

Official answer

45

NTA final key.

Chapter
Relations and Functions
Topic
Sets and Relations
Idea tested
Min-Max Cardinality Boundaries

Same topic in other shifts

All Sets and Relations questions
  1. 5 Apr 2026, Shift 2 · Q21Let A={1,4,7}A=\{1, 4, 7\} and B={2,3,8}B=\{2, 3, 8\}. Then the number of elements, in the relation…MediumNumerical value
  2. 6 Apr 2026, Shift 2 · Q21Let R={(x,y)∈N×N:log⁡e(x+y)≤2}R=\{(x,y)\in\mathbf{N}\times\mathbf{N}:\log_e(x+y)\le2\}. Then the minimum number of elements, required to be added in R to make it…HardNumerical value
  3. 8 Apr 2026, Shift 2 · Q1Consider the relation R on the set {−2,−1,0,1,2}\{-2, -1, 0, 1, 2\} defined by (a,b)∈R(a, b) \in R if and only if 1+ab>01 + ab > 0. Then, among the statements…MediumOther
  4. 2 Apr 2025, Shift 1 · Q12Let A be the set of all functions f:Z→Zf:\mathbf{Z}\to\mathbf{Z} and R be a relation on A such that…EasySingle correct
  5. 3 Apr 2025, Shift 1 · Q1Let A={−3,−2,−1,0,1,2,3}A = \{-3, -2, -1, 0, 1, 2, 3\}. Let R be a relation on A defined by xRyx\mathrm{R}y if and only if 0≤x2+2y≤40 \le x^2 + 2y \le 4. Let ll be…MediumSingle correct
  6. 3 Apr 2025, Shift 2 · Q1Let A={−2,−1,0,1,2,3}A = \{-2, -1, 0, 1, 2, 3\}. Let R be a relation on AA defined by xRyxRy if and only if y=max⁡{x,1}y = \max\{x, 1\}. Let ll be the number of…MediumSingle correct

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.