Micael gets 3 marks for each correct questions and loses 2 marks for e...
let x be the no of correct answer
x+y=30
3x-2y=30
2x+2y=60
5x=90
x=18
View all questions of this testMicael gets 3 marks for each correct questions and loses 2 marks for e...
Solution:
Let the number of correct answers be x and the number of wrong answers be y.
Then, x + y = 30 ...(1) (since he attempted 30 questions in total)
Also, he gets 3 marks for each correct answer and loses 2 marks for each wrong answer. So, his total marks can be written as:
3x - 2y = 30 ...(2)
Simplifying equation (2):
3x = 2y + 30
x = (2/3)y + 10
Substituting this value of x in equation (1):
(2/3)y + 10 + y = 30
(5/3)y = 20
y = 12
Substituting this value of y in equation (1):
x + 12 = 30
x = 18
Therefore, the number of questions he answered correctly is 18. Hence, the correct option is (a).
Micael gets 3 marks for each correct questions and loses 2 marks for e...
A option is write