﻿ In the certain test there are n questions. In this test 2k students gave wrong answers to at least (n – k) questions, where k = 0, 1, 2, …, n. If the total number of wrong answer is 4095, then value of n is  : Kaysons Education

# In The Certain Test There Are n questions. In This Test 2k students Gave Wrong Answers To At Least (n – K) Questions, Where k = 0, 1, 2, …, n. If the Total Number Of Wrong Answer Is 4095, Then Value Of n is

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## Question

### Solution

Correct option is

12

The number of students answering at least r questions incorrectly is 2n – r

∴the number of students answering exactly r(1 ≤ r ≤ n – 1) questions incorrectly is .

Also, the number of students answering all questions wrongly is 2o = 1.

Thus, the total number of wrong answer is

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