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?
By #3, if Granny is an Engineer, then either the Father
or Son is the Doctor, but that violates #1. Also if Mom
is an Engineer, then the son is a Doctor, which also
violates #1. Neither Granny, nor Mom is an Engineer.
The son, who is younger than everyone and a blood
relative of everyone, cannot be an Engineer because that
Granny cannot be a Doctor, because the Father is younger,
and that would violate #2.
If Mom is the Engineer, that violates #3, because she and
her hubby must be related.
Therefore, the Son X is the Doctor, and Father X is the
Posted by Lawrence
on 2003-08-28 21:53:57