CAT 2003 Slot 1 — QA Question 14
Simple EquationsEasy
A test has 50 questions. A student scores 1 mark for a correct answer, −1/3 for a wrong answer, and −1/6 for not attempting a question. If the net score of a student is 32, the number of questions answered wrongly by that student cannot be less than
Answer & solution
Correct answer: 3
- A
6
- B
12
3
- D
9
Solution
Let R, W and N be the number of questions with right answers, questions with wrong answers and not attempted questions respectively.
From the conditions given in the question, we have,
R + W + N = 50 … (i)
R − W/3 − N/6 = 32 … (ii)
Solving equations (i) and (ii), we get,
7R − 242 = W
∴ W will be minimum for R = 35, i.e. W = 3
Hence, option (c).