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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

If

{\;^n}{P_r} = 30240

and

{\;^n}{C_r} = 252

, then the ordered pair

\left( {n,\;r} \right)

is equal to

View answer and explanation

Correct option: B

(10,5)

Option B (10,5) is correct because it satisfies both the permutation and combination equations given in the problem.

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