Sally is evaluating some test papers. There are 80 multiple choice questions in the test. Students get two points for every correct answer and for every wrong answer or any question left blank, one point is deducted from the total score. Mick got 115 points on the test. If x represents the number of questions answered correctly, which equation can be used to find the number of questions he answered correctly?
A.
2x - (80 - x) = 115
B.
x + 115 = 80
C.
x - 115 = 80
D.
x + (80 + x) = 115(my answer)
2x - (80 - x) = 115 (right answer).
the answer is 2x-(80-x)
To solve this problem, let's break it down.
We know that there are 80 multiple choice questions in the test. Students receive two points for every correct answer and lose one point for every wrong answer or any question left blank. Mick got a total score of 115 points.
Let's assume x is the number of questions Mick answered correctly.
So, for every correct answer, Mick gains 2 points. Therefore, the total points he earned from correct answers would be 2x.
For every wrong answer or blank question, Mick loses 1 point. So, the total points lost due to incorrect or blank answers would be (80 - x) since there are 80 questions in total.
Given that Mick's total score is 115, we can set up the equation:
2x - (80 - x) = 115
Now, let's look at the answer choices:
A. 2x - (80 - x) = 115 - This is the correct equation we derived.
B. x + 115 = 80 - This equation is not relevant to the problem since it does not account for the points gained or lost for correct/incorrect answers.
C. x - 115 = 80 - This equation is also not relevant to the problem since it does not accurately reflect the given scenario.
D. x + (80 + x) = 115 - This equation does not account for the points gained or lost for correct/incorrect answers.
Therefore, the correct equation is A. 2x - (80 - x) = 115.