Question

a test has 50 questions. each answer gives 3 marks and each wrong answers gives -2. andrew scores 104 points. work out how he did it

Answer 1

$\textbf{Answer is as follows :}$

Given,

1) A test has 50 question

2) 3 marks are awarded for every correct answer.

3) 2 marks are deducted for every wrong answer

4) Andrew scores 104 points

To find ,
How did he scored 104 marks

Let the number of his correct answers be x

So, no. of wrong answers = 50 - x

Positive marks = 3 × x

Negative marks = -2 × ( 50 - x )

Positive marks + negative marks = Total marks

Now, framing a linear equation in one variable x

3x - 2( 50 - x ) = 104

Now solving for x using transposition

3x - 100 + 2x = 104

5x - 100 = 104

5x = 104 + 100

5x = 204

x = 40.8

50 - x = 50 - 40.8 = 9.2

No. of Q he did correct = 40.8

No. of questions a he did wrong = 9.2

$\textbf{Note : These answers are coming in fractions \\ \\ which means that few questions were \\ \\ having sub questions and he did only a \\ \\ part of it correct.}$