posted by MILDRED .
Please explain the question below.
The members of a certain family are eager waanderers. All ten of them are constantly on the move in one part of the world or another. One Christmas, by some strange coincidence, they all meet in Cairo, Egypt. As they sat down for dinner, a waiter entered and served 2 grandfathers, 2 grandmothers, 3 fathers, 3 mothers, 3 sons, 3 daughters, 2 mothers in law, 2 fathers-in-law, 1 son in-law, 1 daughter in-law, 2 brothers and 2 sisters all ten of them. How many grandparents, parents, daughters?
Start with the two fathers-in-law and two mothers-in-law, the couple and enough children that make exactly 10 people.