This is definately a difficult puzzle but my friend Milly and I managed to solve it after a tiring twenty minutes of confusion.
We worked alone and then when we thought that we had found the answer, we compared them and found out that they were exactly the same.
The answer we found is the following:
Country Bronze Silver Gold Total
France 18 16 7 31
Italy 10 9 8 27
Japan 10 6 9 25
I found that the easiest way to tackle this puzzle was probably to use trial and error as it seems like you are missing a vital clue.
I hope my solution has helped you and to people out there who think it's impossible; it's not as we have proved and we are only in year six!
Thank you for reading and I hope that I have solved your problem!