Question

In a class test (+3) marks are given for every correct answer and (-2) marks are given for any incorrect answer.
1. Radhika scored 20 marks.if she has got 12 correct answers ,how many questions has she attempted incorrectly.
2.mohan scored -5 in this test ,though he got 7 correct answers how many questions has she attempted incorrectly?

Answer 1

Answer:

So, she got 26 marks for the incorrect answer. Now, we know that for every incorrect answer =−2 marks. So, the total marks for incorrect answers = marks for incorrect answer × number of incorrect answers. Hence, the number of incorrect answers is 13.

Answer 2

Step-by-step explanation:

Mark given for the correct answer = 3

mark given to the wrong answer = -2

1. marks scored by Radhika = 20

let , number of questions for which Radhika gave wrong answer be X

marks scored by Radhika = marks obtained on correct answer + mark obtained for wrong answer = 20

marks obtained for correct answer = 12×3 = 36 marks

Mark's obtained for wrong answer = -2X

36 - 2x = 20

2x = 36-20

x = 16/2 = 8

number of questions Radhika attempted incorrectly = 8

2) marks scored by Mohan = -5

let , number of questions for which Mohan gave wrong answer be X

marks scored by Mohan = marks obtained on correct answer + mark obtained for wrong answer = -5

marks obtained for correct answer =7×3=21 marks

Mark's obtained for wrong answer = -2X

21 - 2x = -5

2x = 21+5

2x = 26

x = 13

number of questions Mohan attempted incorrectly = 13