One of Mr. X, his wife, their son and Mr. X's mother is an Engineer and another is a Doctor.
1. If the Doctor is a male, then the Engineer is a male.
2. If the Engineer is younger than the Doctor, then the Engineer and the Doctor are not blood relatives.
3. If the Engineer is a female, then she and the Doctor are blood relatives.
Can you tell who is the Doctor and the Engineer?

(In reply to solution by Steven)

Regardless of whether Mr.X is younger than his wife, his wife could still be the doctor.

The statement
2. If the Engineer is younger than the Doctor, then the Engineer and the Doctor are not blood relatives.
does not say "Only if...", just "If...".

Posted by Charlie on 2003-08-26 08:51:15