Question
Raj scored 140 marks in a test getting 3 marks for each
right answer and losing 1 mark for each wrong answer, had 4 marks been awarded for each correct answer and 2 marks been deducted for each incorrect answer, then Raj would have scored 170 marks. How many question were there in the test?Solution
Let the total right answer is xand Total wrong answer = y Raj scored = 140 marks 3 x - y = 140 …………………(i) Raj scored = 170 marks 4 x - 2 y = 170 …………………(ii) Solving these equations, we get x = 55 So total correct answer = 55 Putting the value of x in eq(i) , we get y = 25 Total wrong answers = 25 so the total number of questions = 55 + 25 = 80Â
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