1. **State the problem:** A man is three times as old as his daughter. In twelve years, he will be twice as old as his daughter. We need to find their present ages. 2. **Define variables:** Let the daughter's present age be $x$ years. 3. **Express the man's age:** Since the man is three times as old as his daughter, his present age is $3x$ years. 4. **Set up the equation for ages in twelve years:** In twelve years, the daughter's age will be $x + 12$ and the man's age will be $3x + 12$. 5. **Use the condition given:** At that time, the man will be twice as old as his daughter, so: $$3x + 12 = 2(x + 12)$$ 6. **Solve the equation:** $$3x + 12 = 2x + 24$$ Subtract $2x$ from both sides: $$3x - 2x + 12 = 24$$ $$x + 12 = 24$$ Subtract 12 from both sides: $$x = 12$$ 7. **Find the man's age:** $$3x = 3 \times 12 = 36$$ 8. **Conclusion:** The daughter is currently 12 years old, and the man is currently 36 years old.