JEE Main 2020MathematicsSets and RelationsMediumNumerical

JEE Main 2020 — Sets and Relations Question with Solution

JEE Main 2020 (06 Sep Shift 1)

Question

Set A has melements and set B has nelements. If the total number of subsets of A is 112 more than the total number of subsets of B, then the value of m·n is___.

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Show full solutionCorrect answer: 28
Correct answer
28

Step-by-step explanation

2m=2n+112
⇒2m-2n=112
⇒2n·2m-n-1=24·23-1
⇒n=4, m=7

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About this question

This is a previous-year question from JEE Main 2020, covering the Sets and Relations chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.