JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Understanding +4 | -1

In a certain test,

a_i

students gave wrong answers to atleast

i

questions, where

i=1,2,3, \ldots, k

. No student gave more than

k

wrong answers. The total number of wrong answers given is

View answer and explanation

Correct option: A

a_1+a_2+\ldots+a_k

Option A (

a_1+a_2+\ldots+a_k

) is correct because it represents the sum of students who gave at least i wrong answers for each i from 1 to k, which equals the total number of wrong answers.

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\left( {m + n} \right)

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n

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