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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

1 of 1

Application +4 | -1

The value of

\sum_{r=1}^{10} r \cdot \frac{{ }^n C_r}{{ }^n C_{r-1}}

is equal to

View answer and explanation

Correct option: A

5(2 n-9)

Option A (

5(2n-9)

) is correct because the summation can be simplified using the properties of combinations and then evaluated.

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