Answer: King Tut was born in 20 B.C. There were 120 years between the birth of King Eros and the death of King Tut, but since their ages amounted to only 100 years, there must have been 20 years when neither existed. This would be a period between the death of King Eros, 40 B.C., and the birth of King Tut, 20 B.C.
King Tut died 120 years after King Eros was born. Their combined age when they died was 100 years. King Eros died in the year 40 B.C. In what year was King Tut born?