Question

Solve this by:

CROSS MULTIPLICATION METHOD​

Answer 1

Answer:

20 questions were there totally

Step-by-step explanation:

given he scored 40 marks

3 for correct answer

1 for wrong answer

case 2

he would have scored 50

if

4 for correct

2 for wrong

lets u consider x as correct answer

and y as wrong answer

case 1

50=4x-2y(we kept as x as we dont know no of correct ans and y as we dont know no of wrong answers)

case 2

40=3x-y

now

    x                  y         1

-2          -50          4         -2

-1           -40           3         -1

cross multiply

x/80-50=y/-150+160=1/-4+6

x/30=y/10=1/2

x=15

y=5

answer is 20 questions

Answer 2

Hope it helps! mark as brainliest