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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

1 of 1

Application +4 | -1

If

{\;^{189}}{C_{35}} + {\;^{189}}{C_x} = {\;^{190}}{C_x}

, then

x

is equal to

View answer and explanation

Correct option: C

36

Option C (36) is correct because it uses the combination identity

{\;^n}{C_r} + {\;^n}{C_{r - 1}} = {\;^{n + 1}}{C_r}

to find the value of x.

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{\;^{n + 2}}{C_8}:{\;^{n - 2}}{P_4} = \frac{{57}}{{16}}

n