Yes, there must be some kind of trick hereThere are 10 people in...

Yes, there must be some kind of trick here
There are 10 people in total. So each can only shake hands with max 8 people (exluding therselves and partner). It quotes that everyone shook hands so minimum number of shakes by a person is 1. So the range of shakes is 1 thru 8. but he asked 9 people, there aren't 9 integers in the range 1-8. Maybe a maid or gay couples as already posited.