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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Medium

1 of 1

Application +4 | -1

Determine

n

, if

{ }^{\text {2n}} C_2:{ }^n C_2=9: 2

.

View answer and explanation

Correct option: A

5

Option A (5) is correct because solving the ratio

{ }^{2n} C_2:{ }^n C_2=9: 2

leads to

n=5

.

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