Question

in an examination a student scores 2 marks for every correct answers and loses 1 mark for every wrong answers if he attempts all 90 Questions and secures 42 marks then the number of questions he attempted correctly is​

Answer 1

Answer:

44

Step-by-step explanation:

let the no of correct answers be x  and no. of wrong answers be y

Given,

x+y=90  = > y = 90 - x  ------------------ [1]

2x- y = 42    ------------------ [2]

Substitute [1] in [2]

2x - (90 - x)= 42

3x - 90= 42

3x = 132

x = 44

So, Number of correct answers = 44