Question

in a class test (+5) marks are given for every correct answer and (-2) marks are given for every incorrect answer and no marks for not attempt any questions ..
(a) Reema score -5 marks by attempting 13 question how many questions has Reema attempted correctly and how many has Reema attempted incorrectly

Answer 1

let x be right answers.

13-x is wrong answers

5x+(13-x)×(-2)=-5

5x-26+2x=-5

7x-21=0

7x=21

x=3.

she attempted 3 right answers

3×5=15

so 10 wrong answers so 10×-2=-20

15+(-20)=-5

hope the answer is helpful.

Answer 2

+5 For Correct Answer

-2 For Incorrect Answer.

Total Questions Reema Attempt=13

Let Correct Attempted Question=X

Then Incorrect Attempt Question=13-x

Total Marks on correct Answer=5(total correct Answer)

=5x

Correct Answer Marks=5x

Incorrect Attempt Question=13-x

Total marks for Incorrect answer

=-2(13-x)

=-26+2x

Total marks=-5

5x+(-26+2x)=-5

5x-26+2x=-5

7x-26=-5

7x=-5+26

7x=21

X=21/7

X=3

Incorrect Attempt Question=13-x

X=3

13-3

=10

Reema Have Attempt $\underline{10}$ Question Incorrectly.