SOLUTION: A student loses a mark for every wrong answer and scores 2 marks for every correct answer. If the answers all the 60 questions in an exam. and secure 39 marks, how many of them wer
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Question 1113041: A student loses a mark for every wrong answer and scores 2 marks for every correct answer. If the answers all the 60 questions in an exam. and secure 39 marks, how many of them were correct Found 3 solutions by ikleyn, stanbon, greenestamps:Answer by ikleyn(52800) (Show Source):
x + y = 60 (1)
2x - y = 39 (2)
---------------------------Add eq(1) and (2) to eliminate y. You will get
3x = 60+39 = 99 ====> x = = 33.
Answer. 33 correct answers. The rest 60-33 = 27 answers are incorrect.
Check. 2*33 - 27 = 39. ! OK !
2 - One equation setup and solution
2x - (60-x) = 39.
3x = 39 + 60 = 99 ====> x = = 33 the same answer.
You can put this solution on YOUR website! A student loses a mark for every wrong answer and scores 2 marks for every correct answer. If the answers all the 60 questions in an exam. and secure 39 marks, how many of them were correct.
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c + w = 60 questions
2c-w = 39 marks
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Add and solve for "c":
3c = 99
c = 33 (# of correct answers)
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w = 60-33 = 27 (# of wrong answers)
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Cheers,
Stan H.
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