Number Of Chairs
Riddle: What's the least number of chairs you would need around a table to sit four fathers, two grandfathers, and four sons?
Answer: Four.
The trick is that the roles overlap. You only need four chairs because the same four people can simultaneously satisfy “four fathers,” “two grandfathers,” and “four sons.” A classic arrangement is: great‑grandfather, grandfather, father, and son. In this setup: The great‑grandfather and the grandfather are both grandfathers. All four can be fathers (the son can have a child not present). All four are also sons of someone. So the least number of chairs is four
Source: https://riddles.com/128
