Set A has m elements and set B has n elements. 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 ______.
Answer (integer)
28
Solution
Number of subsets of A = 2<sup>m</sup>
<br><br>Number of subsets of B = 2<sup>n</sup>
<br><br>Given = 2<sup>m</sup> – 2<sup>n</sup>
= 112
<br><br>$\therefore$ m = 7, n = 4 (2<sup>7</sup> – 2<sup>4</sup>
= 112)
<br><br>$\therefore$ m $\times$ n = 7 $\times$ 4 = 28
About this question
Subject: Mathematics · Chapter: Sets, Relations and Functions · Topic: Sets and Operations
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