SOLUTION: A student loses 3 marks for every wrong answer and scores 2 marks for every correct answer. if he does all the 50 questions in an examination and scores 65 marks, how many of them

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Question 1045128: A student loses 3 marks for every wrong answer and scores 2 marks for every correct answer. if he does all the 50 questions in an examination and scores 65 marks, how many of them were correct? (please explain the method)
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
x = number of correct answers
Since the student answered all 50 questions in the examination,
50-x = number of wrong answers.
If the student loses 3 marks for every wrong answer and scores 2 marks for every correct answer,
his score would be calculated as
2x-3%2850-x%29 .
Since his score was 65 ,
2x-3%2850-x%29=65 .

Solving:
2x-3%2850-x%29=65
2x-3%2A50%2B3x=65
2x-150%2B3x=65
5x-150=65
5x=65%2B150
5x=215
x=215%2F5
x=highlight%2843%29