Question

There are 180 multiple choice questions in a test. A candidate gets 4 marks for every correct answer answer, for every unattempted or wongly answered questioned one mark is deducted from the total score of correct answers. If a candidate scored 450 marks in the test. How many questions did he answered correctly?

Answer 1

I'm assuming the candidate attempted all the questions.

Answer: 126

Step-by-step explanation: Let the number of correct answers be X and the number of incorrect/unattempted answers be Y.

Then, we have

X+Y=180

Marks obtained for correct answers in total = 4X

Marks deducted for incorrect/unattempted answers in total = Y

Total marks obtained = 450

So,

450 = 4X-Y

and we know that

180 = X+Y

Adding these two equations together, we get

450+180 = 4X-Y+X+Y

630 = 5X

X = 126