Here's what I have so far and I don't even know if I'm on the right track at all, so somebody can take this and run with it, fttt this I'm gone.
- There are 10 people total
- The maximum number of people each individual could play DK with is 8 (since they would definitely know themselves and their spouse, but could potentially not have met any of the others).
- The question says that *each* person gave Jason a different answer. I interpret that to mean that he got 9 *distinct* answers (that is, nobody's answer was the same as anybody else's answer).
- There are 9 possible answers, zero through 8.
- However, zero AND 8 could not have BOTH been given as answers. One or the other is possible, but not both. If an attendee played zero games, it means they knew everybody at the party, which means that there could not have been an attendee who played 8 games, because you can't simultaneously have a person who has met everybody and a person who has met nobody.
- So Jason only could have gotten 8 distinct answers.
That's where I'm stuck, and I haven't even gotten to how Anna's answer could be narrowed down from the information given.