Question 1010229
Call their ages NOW, p and c.  Thus
p + c = 30 so we have p = 30 - c
Then
p + 3 = 4(c + 3)
Substitute in and get
30 - c + 3 = 4(c + 3)
33 - c = 4c + 12
21 = 5c
c = 4.2 years
p = 25.8 years