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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

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Analyzing +4 | -1

If

{\;^n}{C_{r - 1}} = 36,{\;^n}{C_r} = 84

and

{\;^n}{C_{r + 1}} = 126,

then

View answer and explanation

Correct option: B

n = 9,r = 3

Option B (

n = 9, r = 3

) is correct because it satisfies the given combinatorial equations when the ratios of consecutive binomial coefficients are calculated.

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