JEE Mains · Maths · STD 11 - 1. set theory
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 \(m \times n\) is
- A \(7\)
- B \(4\)
- C \(28\)
- D \(24\)
Answer & Solution
Correct Answer
(C) \(28\)
Step-by-step Solution
Detailed explanation
\(2^m -2^{ n }=112\) \(m =7, n =4\) \(\left(2^{7}-2^{4}=112\right)\) \(m \times n =7 \times 4=28\)
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