Question: If a man is 45 years old now, how many years ago was he twice as old as his son who is currently 15 years old?
Options:
Correct Answer: 15
Solution:
Let x years ago, the man\'s age was 45 - x and the son\'s age was 15 - x. We have 45 - x = 2(15 - x). Solving gives x = 15.