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 answers.
(i) How many incorrect answers has she attempted?
(ii) How many questions were given in the test?

2

Answers

2016-04-07T20:28:11+05:30
She has attempted 10 incorrect answers
there were 20 questions
2 3 2
2016-04-07T20:35:52+05:30
(i)sona got 10 answers correct.
    1 correct answer = 3 marks
    10 correct answers = 10×3 = 30 marks
but she got only 20
     1 wrong answer = -1 mark
   that means she attempted 10 incorrect answers.
(ii) from (i) she made 10 incorrect answers
     from the question 10 correct answers.
no.of questions in the test= no.of incorrect+ no.of correct answers
                                         = 10+10= 20

2 4 2