Question

Mohan gets 3 marks for each correct question and loses 2 marks for each incorrect question. He attempts 30 questions and obtains 40 marks. Find the number of questions solved correctly by him.

• A. 20
• B. 25
• C. 15
• D. 10

Answer 1

The correct option is A 20

Correct option is (c).
It is given that, Mohan gets 3 marks for each correct answer and loses 2 marks for each wrong answer.
He attempted 30 questions and got 40 marks.
Let the number of questions solved correctly be n.
Then number of wrong questions = 30 − n
∴ 3n − 2(30 − n) = 40
⇒ 3n − 60 + 2n = 40
⇒ 5n = 100
⇒ n = 20

The number of questions solved correctly by Mohan is 20.