Question 48
Linear and Simultaneous EquationsA father is now three times as old as his son. Twelve years ago he was six times as old as his son. How old are the son and the father?
- A.20 and 45
- B.100 and 150
- C.45 and 65
- D.35 and 75
- E.20 and 60.
Show the answer and explanation
Answer: E (20 and 60.)
Explanation
Let the son be y, so the father is 3y. Then 3y − 12 = 6(y − 12), giving 3y = 60 and y = 20. The father is 60.