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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Hard

1 of 1

Application +4 | -1

The number of ways of selecting

n

objects out of

3 n

objects, of which

n

are alike and rest are different, is

View answer and explanation

Correct option: A

2^{2 n-1}+\frac{(2 n-1) !}{n !(n-1) !}

Option A (

2^{2 n-1}+\frac{{(2 n-1) !}}{{n !(n-1) !}}

) is correct because it represents the number of ways to select n objects out of 3n objects, where n are alike and the rest are different.

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