Question

In a class test (+3) marks are given for every correct answer and (-2) marks are given for incorrect answer and no marks for attempting any question. Radhika scored 20 marks. If she has got 12 correct answers, how many questions she has attempted incorrectly ? Mohini scores (-5) marks in this test, though she has got 7 correct answers. How many questions she has attempted incorrectly?​

Answer 1

Answer:

Radhika- 8 questions

Mohini-13 questions

Step-by-step explanation:

a) Radhika- 1) 12 correct answers means marks scored = 12*(+3)=36 mrks for correct answer.

2) Marks scored =20

Correct answers' marks =36

Negative marks=36-20=16

3) 16 marks means no.of questions = 16/2=8 questions

4) Hence 8 questions were answered wrongly

b)Mohini- 1) 7 correct answers means 7*(+3) marks =21 marks

2) Marks scored = -5

correct answers' marks= 21

Negative Marks = 21-(-5)=21+5=26

3) 26 marks means no. of questions =26/2 = 13 questions

4) Hence 13 questions were answered wrongly

Answer 2

Step-by-step explanation:

Solution

Marks awarded for 1 correct answer = + 3

Marks awarded for 1 wrong answer = -2

(i) Radhika scored 20 marks

Total marks awarded for 12 correct answers = 12 × 3 = 36

Marks awarded for incorrect answers = Total score – Total marks awarded for 12 correct answers

= 20 – 36 = ...........

So, the number of incorrect answers made by Radhika = (-16) ÷ (-2) = …….

(ii) Mohini scored -5 marks

Total marks awarded for 7 correct answers = 7 × 3 = 21

Marks awarded for incorrect answers = Total score – Total marks awarded for 7 correct answers

= – 5 – 21 = ............