Question 1203624
 Tina was three times younger than Helen in 2006.
 3t = h 
In 2012 Helen will be 42. 
h + 6 = 42
How old will Tina be in 2012?
:
Six years later
3t+6 = h+6
  h+6=42 therefore
3t + 6 = 42
3t = 42 - 6
3t = 36 
t = 36/12
t = 12 in 2006
Therefore 6 years in 2012, Tina will be 18