Sam, Alex, Charlie, and Jordan are related. One of them is the opposite gender from the other three. Here are some facts:
- Charlie’s only son is either Sam or Alex.
- Jordan’s sister is either Alex or Charlie.
- Jordan is either Sam’s brother or Sam’s only daughter.
Who is the opposite gender from the other three?
Answer
Charlie is female and is of the opposite gender.
If Jordan is Sam’s only daughter, then Jordan cannot have a sister and statement 2 becomes false. Therefore, Jordan must be Sam’s brother and a male.
From statement 1, Charlie’s only son cannot be Sam as Jordan is Sam’s brother, so Charlie’s only son is Alex.
For statement 2, we know that Alex is a male, so Alex cannot be Jordan’s sister. Therefore Charlie is Jordan’s sister.
It’s clear that Sam, Jordan and Charlie are siblings and Alex must be Charlie’s only son.