Read the following passage and solve the questions based on it.
A quiz has three rounds of two questions each. However, the scoring scheme is different in all the three rounds as per the following:
In the first round, each correct answer carries 20 points and each incorrect answer carries a penalty of 10 points. If both the questions in the 1st round are answered correctly a bonus of 10 points is awarded.
In the second round, each correct and incorrect answer gets the same points as in the first round. However an additional penalty of 10 points is awarded if both the questions are answered incorrectly.
In the third round, each right answer fetches 40 points and an incorrect one fetches a penalty of 20 points.
If only two answers are incorrect in the whole quiz, what is the minimum possible score that a contestant can achieve?