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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

Let

x_1, x_2, x_3, \ldots, x_k

be the divisors of positive integer '

n

' (including 1 and

x

). If

x_1+x_2+\ldots+x_k=75

, then

\sum\limits_{i=1}^k \frac{1}{x_i}

is equal to

View answer and explanation

Correct option: D

\frac{75}{n}

Option D (75/n) is correct because the sum of the reciprocals of the divisors is equal to the sum of the divisors divided by n.

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