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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

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Analyzing +4 | -1

Let

S=\{1,2,3, \ldots, n\}

. If

X

denotes the set of all subsets of

S

containing exactly two elements, then the value of

\sum\limits_{{A \in X}}(\min A)

is

View answer and explanation

Correct option: A

{ }^{n+1} C_3

Option A (

{ }^{n+1} C_3

) is correct because it accurately sums the minimum elements of all two-element subsets of S.

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