Question

Pinky scored 40 marks in a test getting 3 marks for each right answer and losing 1 mark for each wrong answer. Had 4 marks been awarded for each correct answer and 2 marks were deducted for each wrong answer, then Pinky again would have scored 40 marks. How many questions were there in the test?

Answer 1

Let No. of correct answer be x
and, No. of incorrect answer be y

We are given,
3x-y = 40 .....................................................(1) {3 marks for each right answer and losing 1 mark for each wrong answer total 40}

and
4x-2y = 40 {4 marks been awarded for each correct answer and 2 marks were deducted for each wrong answer}
2x-y = 20 ................................(2)

By subtracting Eqn. (1) from Eqn. (2)

2x-y = 20 -
(3x-y = 40)

= > -x = -20
so , x= 20

By putting x = 20 in eqn (1)

3(20) - y = 40
so, 60 - y =40
so, y = 20


So Total No of Questions = x + y = 20 + 20
= 40 Answer