Question

In a Mathematics paper there are 10 problem. correct answer carries 5 marks whereas for each incorrect answer 2 marks are deducted from the marks scored. Abdul answered all the questions and but got only 29 marks. find the number of the correct answer given by Abdul.​

Answer 1

Let the total number of correct answer be x

Total number of incorrect answers = 10 - x

Therefore, x*5 + ( 10- x)*(-2) = 29

5x + (-20) + 2x = 29

7x = 29+20

7x = 49

x = 49/7

x = 7

Therefore number of correct answers = 7

Answer 2

Answer:

Ler the no.of right answers be x and

wrong answers be 10-x marks for 1 correct answer is 5

so, 5x marks are obtained for x answers and

-20+2x marks for wrong answers

A.T.Q

5x - 20 + 2x = 29

7x = 49

x=7

so, no.of right answers = 7