Answer:
Now: Carolyn 18 yo, Alfred 12 yo
Explanation:
Use X represent Alfred's age now, then Carolyn's age is (X+6)
6 years ago, their ages should be current age minus 6. So Alfred's age was (X-6), Carolyn's age was ((X+6)-6).
As 6 years ago, Carolyn's age was twice as Alfred's. So
((X+6)-6)=(X-6)×3
X=12 which is Alfred' current age
X+6=18 which is Carolyn' current age