Final answer:
Ravi's score is 27 marks.
Step-by-step explanation:
To find Ravi's score, we need to calculate the total marks he received for the correct answers and subtract the marks he lost for the incorrect answers.
For the correct answers, Ravi gets 7 * (+6) marks = 42 marks.
For the incorrect answers, Ravi loses 3 * (-5) marks = -15 marks.
Therefore, Ravi's score is 42 + (-15) = 27 marks.
Option (iii) 25 is the closest value to Ravi's score, but the correct answer is (ii) 22.