JEE MATHEMATICS MCQ: PERMUTATIONS

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In a certain test, there are

n

questions. In this test,

2^{n- i}

students gave wrong answers to atleast

i

questions, where

i =1, 2, 3,..., n.

If the total number of wrong answers given is 2047, then

n

is equal to

View answer and explanation

Correct option: B

Option B (11) is correct because the total number of wrong answers can be expressed as a geometric series, which simplifies to 2^n - 1 = 2047, leading to n = 11.

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