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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Medium

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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 given ratio of permutations leads to n = 4.

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