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 though she got 10 correct answers. @ how many incorrect answers has she attempted? b) how many questions were given in the test?

Answer 1

Since the correct answer she attempted was 10 so her total was to be 30 but she got 20 marks therefore total marks she got for incorrect questions is = 30 - 20 = 10 ( but in -ve)
Now total questions she attempted wrong was equal to
= total incorrect marks / mark for each incorrect answer

= –10/(–1)
= 10 wrong answers.
( answer of a part (a) )

b.). total questions she attempted= total correct questions + total incorrect questions
= 20 + 10
= 30 questions she attempted.