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Permutations and Combinations question

2021 · 25 Jul · Shift 2 · Q39

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PYQ Library
JEE Main
Mathematics
Permutations and Combinations
2021 · 25 Jul · Shift 2 · Q39

Permutations and Combinations question

2021 · 25 Jul · Shift 2 · Q39

JEE MainMathematicsPermutations and CombinationsMCQ+4 / −1

If

{}^n{P_r} = {}^n{P_{r + 1}}

and

{}^n{C_r} = {}^n{C_{r - 1}}

, then the value of r is equal to :

A
1
B
4
C
2
D
3

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