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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

The positive integer

r

, such that

{ }^{15} {C}_{3 r}={ }^{15} {C}_{r+3}

, is equal to

View answer and explanation

Correct option: A

3

Option A (3) is correct because solving the equation

{}^{15}C_{3r} = {}^{15}C_{r+3}

leads to

r=3

as the only positive integer solution.

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