Mathematics · Sets and Relations

JEE Main 2024 — 30 January, Shift 1 — Question 21

A group of 40 students appeared in an examination of 3 subjects - Mathematics, Physics & Chemistry. It was found that all students passed in at least one of the subjects, 20 students passed in Mathematics, 25 students passed in Physics, 16 students passed in Chemistry, at most 11 students passed in both Mathematics and Physics, at most 15 students passed in both Physics and Chemistry, at most 15 students passed in both Mathematics and Chemistry. The maximum number of students passed in all the three subjects is.

Answer: 10

Numerical answer — enter this value.

Step-by-step solution

figure

11−x≥011-\mathrm{x} \geq 0 (Maths and Physics) x≤11\mathrm{x} \leq 11

x=11\mathrm{x}=11 does not satisfy the data. 11+z≤15⇒z≤411+\mathrm{z} \leq 15 \Rightarrow \mathrm{z} \leq 4

figure

11+y≤15⇒y≤411+\mathrm{y} \leq 15 \Rightarrow \mathrm{y} \leq 4

Now 9−z+0+14−y+z+11+y+5−y−z=409-z+0+14-y+z+11+y+5-y-z=40

⇒y+z=−1\Rightarrow \mathrm{y}+\mathrm{z}=-1

Not possible ⇒x≤10\Rightarrow \mathrm{x} \leq 10

For x=10\mathrm{x}=10

figure

Hence maximum number of students passed in all the three subjects is 10 .

Answer key and solution verified before publishing.

Practise Sets and Relations

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.

Exam
JEE Main 2024
Subject
Mathematics
Chapter
Sets and Relations
Topic
Sets
A group of 40 students appeared in an examination of 3 subjects … | JEE Main 2024 PYQ with Solution · DhiX AI