Question

In an exam a student attempted all the questions. The ratio of incorrect and correct questions is 2 ∶ 3. What more number of questions should be corrected by the student so that the ratio of incorrect and correct becomes 1 ∶ 4, if the total number of questions is 60.

• A. 12
• B. 16
• C. 15
• D. 10

Answer 1

Answer:

A. 12

Total number of incorrect questions = (60/5) × 2 = 24 Total correct questions = 60 – 24 = 36 Let student should be corrected be x incorrect questions = 24 – x Correct questions = 36 + x ⇒ (24 – x)/(36 + x) = 1 ∶ 4 ⇒ 96 – 4x = 36 + x ⇒ 5x = 60 ⇒ x = 12