JEE Main 2021 · MathsMultiple choiceSingle correctMediumCalculation

JEE Main 16 March 2021, Shift 2, Maths Q71

Question 71 of 90 in this shift, Maths question 11 of 30, Section A.

Let

A=\{2,3,4,5,\ldots,30\}

and '

\simeq

' be an equivalence relation on

A\times A

, defined by

(a,b)\simeq(c,d)

, if and only if

ad=bc

. Then the number of ordered pairs which satisfy this equivalence relation with ordered pair (4, 3) is equal to :

(1)5
(2)6
(3)7Official answer
(4)8

Official answer

Option 3

NTA final key.

Chapter: Relations and Functions
Topic: Sets and Relations
Idea tested: Equivalence Relations

Same idea in other shifts

Asked 5× 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 42 of the 174 JEE Main shifts held from 2017 to 2026.