• In an examination, a student scores 4 marks for every correct answer and losses 1 mark for every wrong answer. A student attempted all the 200 questions stud and scored 200 marks. Find the number of questions he answered correctly.

    A) 82

      B) 80

    C) 68

      D) 60

    Correct Answer:
      B) 80

    Description for Correct answer
    Let the number of correct answers be x

    and number of wrong answers be y

    Then, 4x - y = 200 ...(i)

    and x + y = 200 ...(ii)

    On adding Eqs. (i) and (ii). we get

    4x - y = 200

    x + y = 200

    5x = 400

    Therefore, x = 80

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