Approval Ratings

You are a singer. There are $5$ judges in a reality show judging your performance. You know beforehand, from your insider sources, that the $i$-th judge will give you a rating of $A_i$ out of $10$. To be selected, you need an average rating of at least $7$. You can bribe a judge by paying them $100$ gold coins. The judge will then change his rating of your performance to $10$. What is the minim