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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

1 of 1

Application +4 | -1

If

20 \%

of three subsets (i.e., subsets containing exactly three elements ) of the set

A=\left\{a_1, a_2 \cdots a_n\right\}

contain

a_1

, then the value of

n

is

View answer and explanation

Correct option: A

15

Option A (15) is correct because it satisfies the condition that 20% of the three-element subsets of A contain a1.

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n