Question

In an exam each correct answer score 1 mark and each wrong answer reduces 0.25 mark. A candidate got 39 marks by answering 100 questions. How many answers did he answer correctly?

Answer 1

Answer:

With

Step-by-step explanation:

Assuming 90 marks is a score (and not a percentage)

R-right answers

W-wrong

Total questions: R+W=120

Score: R-0.25W=90

System

R+W=120

R-0.25W=90

Subtracting equations leads to

(R+W)-(R-0.25W)=120-90

then

1.25W=30

W=24

so that R=120-24=96

96 is correct

Hope this helps...

Pls MARK IT AS BRAINLIEST

Answer 2

Answer:

let number of questions he answered correctly be X

Number of marks obtained by answering correctly =1×x=X

number of questions he answered incorrect=100-x

number deducted =0.25×(100-x)=25-0.25x

A/Q,

X-25+0.25x=39

1.25x=39+25

1.25x=64

X=64÷1.25

X=51.2