Mia 15
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Report Thread starter 11 months ago
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In multiple choice test of 25 questions, four marks are given for each correct answer and two marks deduced for each wrong answer. one mark deduced for any question not attempted.

James scores 55 marks and wants to know how many questions he got right. He can't remember how many questions he did not attempt, but he doesn't think it was very many. How many questions did James get right?

My working out:

Total questions = 25

Marks awarded for correct answer = +4

Marks awarded for wrong answer = -2

Marks awarded for not attempted = -1

No of questions attempted = q

No of questions correct = c

No of questions wrong = q-c

No of questions not attempted = 25 - q

a) Total marks = 4c - 2(q-c) -1(25-q) = 4c - 2q + 2c - 25 + q = 6c - q - 25

idk if I'm doing it right and what do I do next?
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Theloniouss
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Report 11 months ago
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You need to put your "total marks" expression equal to 55.

Then, consider what c and q have to be. For example, can they be fractions? Can they be negative? Could either be 29?

That should give you your answer
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