Asked by Abhijit
In a question paper, there are 150 questions, each question carrying 2 marks. The total marks are 300. For every wrong answer 0.50 marks will be deducted from the scored marks. If a person has to score 270 marks in a paper, how many questions should be answered correctly?
Answers
Answered by
Reiny
number of correct answers --- x
number of incorrect answers --- 150-x
2x - .5(150-x) = 270
2x - 75 + .5x = 270
2.5x = 345
x = 138
He/she should answer at least 138 questions correctly to have score of at least 270
check:
138(2) - 12(.5) = 270
number of incorrect answers --- 150-x
2x - .5(150-x) = 270
2x - 75 + .5x = 270
2.5x = 345
x = 138
He/she should answer at least 138 questions correctly to have score of at least 270
check:
138(2) - 12(.5) = 270