Let the correct answer be x Incorrect answer = (20 - x) Marks for correct answer = 5 × x Marks for incorrect answer (-2) (20 - x) Student’s score in the examination = 48 Now, 5x + (-2) (20 -x) = 48 5x- 40 + 2x = 48 7x = 84 x = 12 So, the correct answer = 12.