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JEE MATHEMATICS MCQ: PERMUTATIONS

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Application +4 | -1

If

{ }^{2 n+1} P_{n-1}:{ }^{2 n-1} P_n=3: 5

, then

n

is equal to

View answer and explanation

Correct option: A

4

Option A (4) is correct because solving the ratio of permutations leads to a quadratic equation with n=4 as the valid solution.

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