Answer:
Atieno is 36 years old now.
Now: Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â In 12 years:
Atieno    x years         x + 12 years
Son       x/6  years      (x/6 + 12) years
Daughter  x/4  years      (x/4 + 12) years
(x/6 + 12) + (x/4 + 12) = (x+12) - 9
21 = x - x/6 - x/4
21 = 7x/12
7x = 252 Â
x = 36