Question
In a competitive examination containing 200 questions, 2
marks are awarded for every correct answer and 1 mark gets deducted for every wrong answer. If a student attempted all questions and obtained 97 marks, how many wrong answers must he have given?Solution
Let number of questions with right answers = x ∴ No. of questions with wrong answers = 200 – x ∴ Marks obtained for right answers = 2x ∴ Marks deducted for wrong answers = 200 – x ∴ 2x - (200 – x) = 97⇒ 3x = 200 + 97 ⇒ 3x = 297 ∴ x = 99 ∴ No. of questions with wrong answers (200 – 99) = 101
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52   83   114   ?   176    207
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