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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

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Application +4 | -1

If

{ }^{{m}+{n}} P_2=90

and

{ }^{{m}-{n}} P_2=30

, then

(m, n)

is equal to

View answer and explanation

Correct option: B

(8,2)

Option B ((8,2)) is correct because solving the system of equations derived from the permutation formulas yields m=8 and n=2.

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