Question

There are 100 questions in a question paper, each carrying 2 marks. But there is a negative making. 1 mark is deducted for each question answered incorrectly. A student answering all the questions got 80 marks. The number of questions correctly answered by him is
1. 70
2. 60
3. 80
4. 75

Answer 1

Correct Answer - Option 2 : 60

Given:

Total number of question is 100

Total marks obtained by student is 80

Calculation:

Let the number of correct question be x

The number of incorrect question = (100 - x)

According to the question;

⇒ 2 × x - 1(100 - x) = 80

⇒ 2x + x - 100 = 80

⇒ 3x = 180

⇒ x = 60

∴ The number of questions correctly answered by him is 60.