Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Relations and Functions

Question:

Two finite sets have m and n elements. The total number of subsets of the first set is 56 more than the total number of subsets of second set. The values of m and n are

Options:

7, 6

6, 3

5, 1

8, 7

Correct Answer:

6, 3

Explanation:

$2^m–2^n= 56⇒2^n(2^{m-n}-1)=2^3×7$

by comparison $n=3$

$2^{m-3}-1=7⇒2^{m-3}=8$

$⇒m-3=3⇒m=6$

m = 6 and n = 3