Home
Class 12
MATHS
In a certain test, there are n questions...

In a certain test, there are n questions. In this test, `2^(n-k)` students gave wrong answers to atleast k questions, where k=1,2,3, . . ,. If the total number of wrong answers given in 127, then the value of n is

A

11

B

12

C

13

D

15

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Similar Questions

Explore conceptually related problems

In a certain test, there are n question. In the test, 2^(n-i) students gave wrong answers to at least i questions, where i=1, 2,.............,n if the total number of wrong answers given is 2047, then n is equal to a. 10 b. 11 c. 12 d. 13

In a certain test, a students gave wrong answers to at least i questions, where i = 1, 2, ..., k . No student gave more than k wrong answers. The total number of wrong answers given is

A test contains 10 true/false questions. A correct answer is awarded 2 marks, a wrong answer -1 and a question not answered is awarded 0. A student attempts 7 questions and gets 8 marks. How many questions did the student answer correctly?

In an exam , 3.5 points are awarded for evey correct answer and 0.45 points are deducted for every wrong answer. If out of N question , a boy answers at least 4 questions wrong and at most 8 questions wrong ,which of the following correctly gives the correct range of score ,S, he can get in the exam ?

Let f(n)= sum_(k=1)^(n) k^2 ^"(n )C_k)^ 2 then the value of f(5) equals

In an AP, If S_(n)=3n^(2)+5n and a_(k)=164, then find the value of k.

In an AP, If S_(n)=3n^(2)+5n and a_(k)=164, then find the value of k.

In answering a question on a multiple choice test, a student either knows the answer or guesses. Let 3/5 be the probability that he knows the answer and 2/5 be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability 1/3 , what is the probability that the student knows the answer given that he answered it correctly

A test paper has 20 multiple-choice questions. Each correct answer is awarded 3 marks but -2 marks are given for every wrong answer. No marks are awarded or deducted for questions that are not attempted. a. Sia attempts all questions. She gets only 12 questions correct. How many marks did she score in this test? b. Rajshree scores 5 marks in a test. If she answers 7 questions correctly, find the number of questions she did not answer correctly, and also the number of questions she did not attempt.

In a class test containing 10 questions, every correct answer is awarded 5 marks, every incorrect answer is awarded (-3) marks, and 0 marks are awarded for every questions not attempted. A student gets 4 questions right, 3 questions wrong, and leaves 3 questions unattempted. What is his score?