Question

In a test +3 marks are given for every correct answer and -1 mark are given for every incorrect answer. Sona attempted all the questions and scored +20 marks though she got 10 correct answes. @ how many incorrect answers has she attempted ? b) how many questions were given in the test?

Answer 1

           As Sona had attempted all the questions and she got 10 correct answer but 20 marks for them. 

Thus 3 marks for each correct answer : 10*3= 30 marks for correct .
       But given that she got only 20 marks means 30- 10 = 20.
       It means that she got 10 incorrect answers and -10 for those answers.

a) Thus Sona has attempted 10 incorrect answers.
b) Total 20 questions were given in the test.

Thank You!