In an examination, a student scores 6 marks for every correct answer and loses 4 marks for every wrong answer. If he attempted 80 questions and obtained 310 marks, how many questions did he attempted correctly?

Explanation

We can get the equation for marks as, Marks = 6x - 4y where x= correct answer and y= wrong answer We have to try for each and individual option. For 59: 6*59 - 21*4 = 270 For 67: 6*67 - 4*13 = 350 For 65: 6*65 - 4*15 = 330 For 61: 6*61 - 4*19 = 290 For 63: 6*63 - 4*17 = 310 Option C is the answer.